Table of Contents
What legal form your business has and why it changes everything
The accounting obligations of the sole trader dealership
The accounting obligations of the dealership SL (Limited Company)
The record books that a car dealership must keep
The tax forms that must be submitted and when
How to separate vehicle expenses from general expenses
How to prepare and send information to the agency
How to reconcile receipts and record expenses correctly
Deductible expenses that many dealerships do not apply
When to manage accounting yourself and when not to
Dealcar and dealership accounting control
Frequently asked questions
What legal form your business has and why it changes everything
The accounting of a dealership depends almost entirely on its legal form. A sole trader (autónomo) and a limited company (sociedad limitada) have different obligations, pay different taxes and keep books with different requirements.
The sole trader pays IRPF (Personal Income Tax). Their business income and expenses are declared in the annual tax return (form 100) along with the rest of their personal income. They are obliged to keep record books of income, expenses, investment assets and, if they apply the REBU (Special Scheme for Second-Hand Goods), the REBU operations record book. They are not obliged to keep formal accounting in accordance with the General Accounting Plan, although they can do so voluntarily.
The limited company pays Corporate Tax (form 200, annual presentation). It is obliged to keep accounting in accordance with the General Accounting Plan: journal book, inventory book and annual accounts. It must deposit the annual accounts in the Mercantile Registry every year. The level of accounting requirements is significantly higher than for the sole trader.
Most small or medium-sized independent car dealers operate as sole traders or as single-member SLs. The choice between one and the other has tax implications that should be reviewed with an advisor when turnover exceeds 40,000 or 50,000 euros of net profit, which is the point where Corporate Tax can be more advantageous than IRPF.
The accounting obligations of the sole trader dealership
A dealership operating as a sole trader is not obliged to keep double-entry bookkeeping or to comply with the General Accounting Plan. Their obligations are simpler but no less important.
They must keep four record books. The sales and income book records all invoices issued, with date, number, customer, taxable base and VAT rate. The purchases and expenses book records all invoices received, with the same data. The investment assets book records the business assets that are depreciated: computer equipment, tools, facilities. And if the REBU applies, the REBU operations record book, which is a separate record with the specific details of each transaction under that scheme.
These books do not have to be submitted to the Tax Agency periodically, but they must be available in the event of an inspection. The obligation to keep them is four years from the submission of the corresponding tax return.
The sole trader's accounting also includes the quarterly monitoring of VAT returns and instalment payments of IRPF, which are the mechanisms by which the sole trader advances part of what they must pay in the annual return to the Tax Agency.
The accounting obligations of the dealership SL
An SL has stricter accounting obligations. It is obliged to keep accounting in accordance with the General Accounting Plan or, if it is a small company, in accordance with the General Accounting Plan for Small and Medium-Sized Enterprises.
That means keeping the journal book (which records all business transactions in chronological order), the inventory and annual accounts book (which includes the balance sheet, the profit and loss account and the notes) and, if the business has several partners or relevant corporate agreements, the minutes book.
The annual accounts must be deposited in the Mercantile Registry within six months following the close of the financial year (usually before 30 June for financial years closing on 31 December). Failure to make this deposit can lead to penalties and the recording of the closure of the registry sheet in the Registry, which prevents registering any other corporate act.
The SL also pays Corporate Tax, with a general rate of 25% on profit (or 23% for companies with turnover under one million euros and with at least one worker). Instalment payments are made in forms 202 (in April, October and December) as an advance on the annual tax.
The record books that a car dealership must keep
Regardless of the legal form, there are record books that are of particular relevance to the second-hand car dealership.
The record book of invoices issued must include all sales, both those carried out under the REBU (without VAT breakdown) and those under the general scheme (with VAT broken down). It is the document that backs up the quarterly form 303.
The record book of invoices received includes all purchases with a VAT invoice: cars acquired from companies or sole traders with VAT, preparation expenses, portals, tools and any other expense with an invoice. The input VAT on these invoices is what can be deducted in form 303.
The REBU operations record book is specific to the sector. For each transaction under the REBU, it must include the date of purchase and sale, the details of the private seller (name, ID, address), the description of the vehicle (make, model, license plate, VIN), the purchase price, the sale price, the gross margin and the VAT calculated on that margin. This book is what the Tax Agency reviews in an inspection to verify that the REBU has been applied correctly.
Check what the REBU record book must include and how to organize it.
Keeping this book up to date, transaction by transaction, is what allows preparing the quarterly form 303 without errors and responding to any tax query with organized documentation.
The tax forms that must be submitted and when
The tax calendar of an independent dealership has several forms to submit on a regular basis. The deadlines are fixed and failure to comply generates surcharges.
Form 303 is the quarterly VAT return. It is submitted four times a year, in the first 20 days of April, July and October, and in the first 30 days of January (for the fourth quarter). In it, the output VAT amounts (sales under general scheme) and the REBU taxable bases are declared, and they are offset against the deductible input VAT (purchases with VAT invoice). The result can be to pay or to offset.
Read also how the REBU margin is calculated and what expenses reduce it.
Form 390 is the annual VAT summary. It is submitted in January of the following year and consolidates the four quarters of the year. It does not generate any additional payment: it is an informative summary.
Form 347 is the annual declaration of transactions with third parties for amounts exceeding 3,005.06 euros. If the dealership has professional suppliers or customers with whom it has operated above that figure throughout the year, it must declare them. It is submitted in February of the following year.
For sole traders, form 130 is the quarterly instalment payment of IRPF (20% on the net income of the quarter, minus previous payments). It is submitted within the same deadlines as form 303.
For SLs, form 202 is the instalment payment of Corporate Tax. It is submitted in April, October and December, calculated on the basis of the last closed financial year or on the result of the accumulated period according to the chosen method.
How to separate vehicle expenses from general expenses
This is the most important accounting distinction for a second-hand car dealership and the one most frequently mismanaged when there is no specific system.
Vehicle expenses are those directly linked to a specific car and which form part of the actual cost of that transaction: the purchase price, transport from origin, mechanical or bodywork repairs carried out before the sale, the transfer agency fees and the ITV (MOT) if it expired. These expenses must be recorded in the file of the specific vehicle, not in a general expenses drawer. They are the ones that determine the actual net margin of each transaction and the ones that the Tax Agency can request in a REBU inspection.
General expenses are those that are not attributable to a specific vehicle but to the operation of the business as a whole: local rent, fees for publication portals, management software, payroll, business insurance, utilities and training expenses. These expenses are tax-deductible as business activity expenses, but they do not enter into the calculation of the REBU margin.
The correct separation has two practical implications. The first is fiscal: including general expenses in the calculation of the REBU margin improperly reduces the taxable base and can generate a tax reassessment. The second is managerial: if vehicle expenses and general expenses are mixed up, the calculation of the real margin per transaction is not reliable and purchasing decisions are made with distorted information.
Also check how to prepare the accounting documentation for each vehicle.
The most efficient way to make that separation is to have a system that allows registering each expense directly in the file of the corresponding vehicle, instead of classifying it a posteriori at the end of the month.
How to prepare and send information to the agency
The quality of the work done by the agency (gestoría) depends directly on the quality of the information it receives. An agency that reaches the end of the quarter with messy data, unclassified invoices and undocumented transactions takes longer, charges more and makes more mistakes than one that receives organized data.
The minimum information that the agency needs at the end of each quarter consists of four blocks. The first is the list of sales for the period with the sale price, the tax scheme applied (REBU or general) and the taxable base or margin as appropriate. The second is the list of purchases with a broken-down VAT invoice for the period, with the deductible input VAT for each. The third is the summary of the REBU record book with the positive and negative margins of the quarter. The fourth is the list of general expenses for the period with their invoices.
If the dealership arrives with those four blocks organized, the agency can prepare form 303 in less than an hour. If it arrives with unstructured data, the agency has to do that classification work, which raises the cost and increases the risk of errors.
Read what a REBU billing program must comply with to facilitate the work of the agency.
The way to export that information depends on the management system used by the dealership. A DMS specific to car sales can generate those four blocks automatically at the end of the quarter in the format needed by the agency. With Excel or with general accounting software, that export must be built manually every quarter.
How to reconcile receipts and record expenses correctly
Reconciliation between receipts recorded in the system and movements in the bank account is the process that detects unrecorded operations, duplicate payments or paid invoices that have no record in the system.
For a dealership, reconciliation is particularly important in three types of operations. Deposits and reserves: a partial payment received before the delivery of the vehicle is not a sale, it is a payment on account. If it is recorded as a sale, the VAT is accrued early and form 303 will be incorrect. Deposits must be recorded as advances and the sale must be closed at the time of delivery. Cash expenses: cash payments of small expenses (petrol for a transport, an urgent spare part, an administrative fee) that do not have an invoice or only have a receipt must be recorded anyway, with the receipt as a minimum supporting document. If they are not recorded, the expense is lost and the declared profit is higher than actual. Financier payments: when the sale is financed, the payment comes from the financier instead of the buyer. The reconciliation between the registered sale, the finance contract and the financier payment must be clear to avoid open operations in the system that are actually already paid.
The registration of expenses with a receipt (without invoice) has a specific tax treatment: they are deductible as an expense if there is a receipt and the activity of the expense is related to the business, but they do not generate deductible input VAT because they do not have a full invoice. Registering them correctly avoids confusion at the quarterly close.
Deductible expenses that many dealerships do not apply
There are expenses that many car dealers do not deduct because they do not know they can or because they do not document them correctly.
Vehicle reconditioning expenses (small mechanical repairs, cleaning, aesthetic preparation) are expenses directly attributable to each transaction and are deductible as cost of goods. They must be documented with an invoice from the workshop or supplier.
The costs of portals, management tools, software subscriptions and procurement platforms are running business expenses and are deductible with an invoice.
Training expenses related to the activity (vehicle valuation courses, management training, attendance at industry trade fairs) are deductible if they are directly related to the business.
The use of one's own vehicle for the dealership's activity (travel to auctions, car collection, client visits) is partially deductible for sole traders if professional use is documented. For companies, vehicles assigned to the activity have VAT deduction and depreciation.
Interest on stock finance lines or loans linked to the business is a deductible financial expense.
Also check the hidden costs of a dealership that eat up the margin.
When to manage accounting yourself and when not to
A car dealer who sells between 5 and 15 cars a month can manage their record books independently if they have a management system that automates the classification of transactions. The agency's work in that case is limited to the quarterly submission of forms and the annual close.
From 20 or 30 transactions a month, or when there are employees, the volume of management makes delegating to a specialized agency or consultancy more economically efficient than devoting the owner's time to accounting. The usual cost of an agency for a dealership of that size is between 150 and 400 euros per month depending on the volume and complexity.
What the agency cannot do for the dealership is keep the transaction record books up to date in real time. That requires the dealership to record each purchase and each sale at the moment they occur, with the complete information. If it arrives at the agency with the data in order, the work of submitting forms is fast and cheap. If it arrives with messy or incomplete data, the cost of the agency rises and the risk of errors also increases.
Dealcar and dealership accounting control
Dealcar automatically records each purchase and sale transaction with the necessary data for accounting: tax scheme (REBU or general), purchase price, reconditioning costs, sale price and margin. The REBU operations record book is updated with each transaction without additional manual work.
Check how the integrated agency of Dealcar works.
That means the dealership reaches each quarter with the data already organized, ready for the agency to prepare the forms without having to reconstruct the information of the last three months.
If you want to see how it works, visit the electronic invoicing page for Dealcar dealerships and request a demo.
Frequently asked questions
Does a sole trader dealership have to keep double-entry bookkeeping?
No. The sole trader is not obliged to keep accounting in accordance with the General Accounting Plan. Their obligations are the record books of income, expenses, investment assets and REBU transactions. Double-entry bookkeeping (with journal book and annual accounts) is mandatory for commercial companies.
What happens if I do not submit form 303 on time?
The Tax Agency applies a surcharge for late submission without prior request: 1% if submitted within the first month, increasing by an additional 1% for each full month of delay up to the twelfth month, and 15% after one year. If there is a prior request from the Tax Agency, the surcharge rises to 25% plus late-payment interest.
Do I need a specific accounting program for dealerships?
For the formal accounting of an SL, an approved accounting program is recommended. For the record books of a sole trader, a dealership-specific management system that automatically classifies transactions and generates the REBU record book is sufficient for daily operations. The agency can work with the information exported from that system.
How long must accounting books be kept?
The general period for keeping accounting and tax documents is four years from the submission of the corresponding tax return (the general tax limitation period). For documents proving transactions with depreciable assets, the period extends for the duration of the depreciation plus an additional four years. In case of doubt, keeping them for ten years is a prudent practice.
Table of Contents
What legal form your business has and why it changes everything
The accounting obligations of the sole trader dealership
The accounting obligations of the dealership SL (Limited Company)
The record books that a car dealership must keep
The tax forms that must be submitted and when
How to separate vehicle expenses from general expenses
How to prepare and send information to the agency
How to reconcile receipts and record expenses correctly
Deductible expenses that many dealerships do not apply
When to manage accounting yourself and when not to
Dealcar and dealership accounting control
Frequently asked questions
What legal form your business has and why it changes everything
The accounting of a dealership depends almost entirely on its legal form. A sole trader (autónomo) and a limited company (sociedad limitada) have different obligations, pay different taxes and keep books with different requirements.
The sole trader pays IRPF (Personal Income Tax). Their business income and expenses are declared in the annual tax return (form 100) along with the rest of their personal income. They are obliged to keep record books of income, expenses, investment assets and, if they apply the REBU (Special Scheme for Second-Hand Goods), the REBU operations record book. They are not obliged to keep formal accounting in accordance with the General Accounting Plan, although they can do so voluntarily.
The limited company pays Corporate Tax (form 200, annual presentation). It is obliged to keep accounting in accordance with the General Accounting Plan: journal book, inventory book and annual accounts. It must deposit the annual accounts in the Mercantile Registry every year. The level of accounting requirements is significantly higher than for the sole trader.
Most small or medium-sized independent car dealers operate as sole traders or as single-member SLs. The choice between one and the other has tax implications that should be reviewed with an advisor when turnover exceeds 40,000 or 50,000 euros of net profit, which is the point where Corporate Tax can be more advantageous than IRPF.
The accounting obligations of the sole trader dealership
A dealership operating as a sole trader is not obliged to keep double-entry bookkeeping or to comply with the General Accounting Plan. Their obligations are simpler but no less important.
They must keep four record books. The sales and income book records all invoices issued, with date, number, customer, taxable base and VAT rate. The purchases and expenses book records all invoices received, with the same data. The investment assets book records the business assets that are depreciated: computer equipment, tools, facilities. And if the REBU applies, the REBU operations record book, which is a separate record with the specific details of each transaction under that scheme.
These books do not have to be submitted to the Tax Agency periodically, but they must be available in the event of an inspection. The obligation to keep them is four years from the submission of the corresponding tax return.
The sole trader's accounting also includes the quarterly monitoring of VAT returns and instalment payments of IRPF, which are the mechanisms by which the sole trader advances part of what they must pay in the annual return to the Tax Agency.
The accounting obligations of the dealership SL
An SL has stricter accounting obligations. It is obliged to keep accounting in accordance with the General Accounting Plan or, if it is a small company, in accordance with the General Accounting Plan for Small and Medium-Sized Enterprises.
That means keeping the journal book (which records all business transactions in chronological order), the inventory and annual accounts book (which includes the balance sheet, the profit and loss account and the notes) and, if the business has several partners or relevant corporate agreements, the minutes book.
The annual accounts must be deposited in the Mercantile Registry within six months following the close of the financial year (usually before 30 June for financial years closing on 31 December). Failure to make this deposit can lead to penalties and the recording of the closure of the registry sheet in the Registry, which prevents registering any other corporate act.
The SL also pays Corporate Tax, with a general rate of 25% on profit (or 23% for companies with turnover under one million euros and with at least one worker). Instalment payments are made in forms 202 (in April, October and December) as an advance on the annual tax.
The record books that a car dealership must keep
Regardless of the legal form, there are record books that are of particular relevance to the second-hand car dealership.
The record book of invoices issued must include all sales, both those carried out under the REBU (without VAT breakdown) and those under the general scheme (with VAT broken down). It is the document that backs up the quarterly form 303.
The record book of invoices received includes all purchases with a VAT invoice: cars acquired from companies or sole traders with VAT, preparation expenses, portals, tools and any other expense with an invoice. The input VAT on these invoices is what can be deducted in form 303.
The REBU operations record book is specific to the sector. For each transaction under the REBU, it must include the date of purchase and sale, the details of the private seller (name, ID, address), the description of the vehicle (make, model, license plate, VIN), the purchase price, the sale price, the gross margin and the VAT calculated on that margin. This book is what the Tax Agency reviews in an inspection to verify that the REBU has been applied correctly.
Check what the REBU record book must include and how to organize it.
Keeping this book up to date, transaction by transaction, is what allows preparing the quarterly form 303 without errors and responding to any tax query with organized documentation.
The tax forms that must be submitted and when
The tax calendar of an independent dealership has several forms to submit on a regular basis. The deadlines are fixed and failure to comply generates surcharges.
Form 303 is the quarterly VAT return. It is submitted four times a year, in the first 20 days of April, July and October, and in the first 30 days of January (for the fourth quarter). In it, the output VAT amounts (sales under general scheme) and the REBU taxable bases are declared, and they are offset against the deductible input VAT (purchases with VAT invoice). The result can be to pay or to offset.
Read also how the REBU margin is calculated and what expenses reduce it.
Form 390 is the annual VAT summary. It is submitted in January of the following year and consolidates the four quarters of the year. It does not generate any additional payment: it is an informative summary.
Form 347 is the annual declaration of transactions with third parties for amounts exceeding 3,005.06 euros. If the dealership has professional suppliers or customers with whom it has operated above that figure throughout the year, it must declare them. It is submitted in February of the following year.
For sole traders, form 130 is the quarterly instalment payment of IRPF (20% on the net income of the quarter, minus previous payments). It is submitted within the same deadlines as form 303.
For SLs, form 202 is the instalment payment of Corporate Tax. It is submitted in April, October and December, calculated on the basis of the last closed financial year or on the result of the accumulated period according to the chosen method.
How to separate vehicle expenses from general expenses
This is the most important accounting distinction for a second-hand car dealership and the one most frequently mismanaged when there is no specific system.
Vehicle expenses are those directly linked to a specific car and which form part of the actual cost of that transaction: the purchase price, transport from origin, mechanical or bodywork repairs carried out before the sale, the transfer agency fees and the ITV (MOT) if it expired. These expenses must be recorded in the file of the specific vehicle, not in a general expenses drawer. They are the ones that determine the actual net margin of each transaction and the ones that the Tax Agency can request in a REBU inspection.
General expenses are those that are not attributable to a specific vehicle but to the operation of the business as a whole: local rent, fees for publication portals, management software, payroll, business insurance, utilities and training expenses. These expenses are tax-deductible as business activity expenses, but they do not enter into the calculation of the REBU margin.
The correct separation has two practical implications. The first is fiscal: including general expenses in the calculation of the REBU margin improperly reduces the taxable base and can generate a tax reassessment. The second is managerial: if vehicle expenses and general expenses are mixed up, the calculation of the real margin per transaction is not reliable and purchasing decisions are made with distorted information.
Also check how to prepare the accounting documentation for each vehicle.
The most efficient way to make that separation is to have a system that allows registering each expense directly in the file of the corresponding vehicle, instead of classifying it a posteriori at the end of the month.
How to prepare and send information to the agency
The quality of the work done by the agency (gestoría) depends directly on the quality of the information it receives. An agency that reaches the end of the quarter with messy data, unclassified invoices and undocumented transactions takes longer, charges more and makes more mistakes than one that receives organized data.
The minimum information that the agency needs at the end of each quarter consists of four blocks. The first is the list of sales for the period with the sale price, the tax scheme applied (REBU or general) and the taxable base or margin as appropriate. The second is the list of purchases with a broken-down VAT invoice for the period, with the deductible input VAT for each. The third is the summary of the REBU record book with the positive and negative margins of the quarter. The fourth is the list of general expenses for the period with their invoices.
If the dealership arrives with those four blocks organized, the agency can prepare form 303 in less than an hour. If it arrives with unstructured data, the agency has to do that classification work, which raises the cost and increases the risk of errors.
Read what a REBU billing program must comply with to facilitate the work of the agency.
The way to export that information depends on the management system used by the dealership. A DMS specific to car sales can generate those four blocks automatically at the end of the quarter in the format needed by the agency. With Excel or with general accounting software, that export must be built manually every quarter.
How to reconcile receipts and record expenses correctly
Reconciliation between receipts recorded in the system and movements in the bank account is the process that detects unrecorded operations, duplicate payments or paid invoices that have no record in the system.
For a dealership, reconciliation is particularly important in three types of operations. Deposits and reserves: a partial payment received before the delivery of the vehicle is not a sale, it is a payment on account. If it is recorded as a sale, the VAT is accrued early and form 303 will be incorrect. Deposits must be recorded as advances and the sale must be closed at the time of delivery. Cash expenses: cash payments of small expenses (petrol for a transport, an urgent spare part, an administrative fee) that do not have an invoice or only have a receipt must be recorded anyway, with the receipt as a minimum supporting document. If they are not recorded, the expense is lost and the declared profit is higher than actual. Financier payments: when the sale is financed, the payment comes from the financier instead of the buyer. The reconciliation between the registered sale, the finance contract and the financier payment must be clear to avoid open operations in the system that are actually already paid.
The registration of expenses with a receipt (without invoice) has a specific tax treatment: they are deductible as an expense if there is a receipt and the activity of the expense is related to the business, but they do not generate deductible input VAT because they do not have a full invoice. Registering them correctly avoids confusion at the quarterly close.
Deductible expenses that many dealerships do not apply
There are expenses that many car dealers do not deduct because they do not know they can or because they do not document them correctly.
Vehicle reconditioning expenses (small mechanical repairs, cleaning, aesthetic preparation) are expenses directly attributable to each transaction and are deductible as cost of goods. They must be documented with an invoice from the workshop or supplier.
The costs of portals, management tools, software subscriptions and procurement platforms are running business expenses and are deductible with an invoice.
Training expenses related to the activity (vehicle valuation courses, management training, attendance at industry trade fairs) are deductible if they are directly related to the business.
The use of one's own vehicle for the dealership's activity (travel to auctions, car collection, client visits) is partially deductible for sole traders if professional use is documented. For companies, vehicles assigned to the activity have VAT deduction and depreciation.
Interest on stock finance lines or loans linked to the business is a deductible financial expense.
Also check the hidden costs of a dealership that eat up the margin.
When to manage accounting yourself and when not to
A car dealer who sells between 5 and 15 cars a month can manage their record books independently if they have a management system that automates the classification of transactions. The agency's work in that case is limited to the quarterly submission of forms and the annual close.
From 20 or 30 transactions a month, or when there are employees, the volume of management makes delegating to a specialized agency or consultancy more economically efficient than devoting the owner's time to accounting. The usual cost of an agency for a dealership of that size is between 150 and 400 euros per month depending on the volume and complexity.
What the agency cannot do for the dealership is keep the transaction record books up to date in real time. That requires the dealership to record each purchase and each sale at the moment they occur, with the complete information. If it arrives at the agency with the data in order, the work of submitting forms is fast and cheap. If it arrives with messy or incomplete data, the cost of the agency rises and the risk of errors also increases.
Dealcar and dealership accounting control
Dealcar automatically records each purchase and sale transaction with the necessary data for accounting: tax scheme (REBU or general), purchase price, reconditioning costs, sale price and margin. The REBU operations record book is updated with each transaction without additional manual work.
Check how the integrated agency of Dealcar works.
That means the dealership reaches each quarter with the data already organized, ready for the agency to prepare the forms without having to reconstruct the information of the last three months.
If you want to see how it works, visit the electronic invoicing page for Dealcar dealerships and request a demo.
Frequently asked questions
Does a sole trader dealership have to keep double-entry bookkeeping?
No. The sole trader is not obliged to keep accounting in accordance with the General Accounting Plan. Their obligations are the record books of income, expenses, investment assets and REBU transactions. Double-entry bookkeeping (with journal book and annual accounts) is mandatory for commercial companies.
What happens if I do not submit form 303 on time?
The Tax Agency applies a surcharge for late submission without prior request: 1% if submitted within the first month, increasing by an additional 1% for each full month of delay up to the twelfth month, and 15% after one year. If there is a prior request from the Tax Agency, the surcharge rises to 25% plus late-payment interest.
Do I need a specific accounting program for dealerships?
For the formal accounting of an SL, an approved accounting program is recommended. For the record books of a sole trader, a dealership-specific management system that automatically classifies transactions and generates the REBU record book is sufficient for daily operations. The agency can work with the information exported from that system.
How long must accounting books be kept?
The general period for keeping accounting and tax documents is four years from the submission of the corresponding tax return (the general tax limitation period). For documents proving transactions with depreciable assets, the period extends for the duration of the depreciation plus an additional four years. In case of doubt, keeping them for ten years is a prudent practice.
