Index
Why the REBU registry book is mandatory and the risk of not keeping it
What information each entry must include
How the book is structured: format and organisation
When to record each transaction
The REBU registry book in mixed operations: REBU and general regime
How the book is used in the quarterly VAT return
How long it must be kept for
Tools to keep the registry book without manual work
Dealcar and the automated REBU registry book
Frequently asked questions
Why the REBU registry book is mandatory and the risk of not keeping it
Article 138 of the VAT Regulations establishes the obligation to keep a specific registry book for transactions carried out under the REBU. It is not a recommendation: it is a legal obligation for any taxable person applying this scheme.
The REBU registry book serves two functions. The first is specific to the dealership: it allows for the correct calculation of the taxable base for each quarter and the preparation of form 303 without errors. The second is the function of proof before the Tax Agency: in the event of an inspection, the registry book is the document that proves that the REBU has been correctly applied to each specific transaction.
The risk of not keeping it, or keeping it in an incomplete state, is that the Tax Agency can reject the application of the REBU to all transactions of the inspected period and recalculate the VAT by applying the general scheme to the full sale price. In that case, the additional tax debt plus interest and surcharges can be significant, especially in high-volume businesses.
Check the complete REBU guide for car dealerships.
What information each entry must include
Each transaction recorded in the REBU registry book must include a minimum set of data established by the VAT Regulations. The recommended practice is to include more than the legal minimum to have complete documentation in case of an inspection.
The mandatory data per transaction are: the internal reference number of the transaction, the date of acquisition of the asset and the date of transfer, the name and surname or company name of the supplier (the person or company from whom the vehicle was purchased), the NIF or NIE of the supplier, the description of the asset (make, model and registration number of the vehicle), the acquisition price (what was paid to the supplier), the sale price (what the final buyer paid), and the profit margin (the difference between the sale price and the acquisition price, which is the REBU taxable base).
In addition to the minimum data, it is advisable to also record the vehicle's VIN (chassis number), the invoice or purchase receipt number and the sales invoice number, and a note on whether the vehicle was purchased from a private individual, from another dealership under REBU, or from a company with no possibility of passing on VAT. This last note justifies why the transaction is eligible for the REBU.
How the book is structured: format and organisation
The VAT Regulations do not impose a specific format for the REBU registry book. It can be a physical book, a spreadsheet, or a digital record generated by management software, provided that it contains the mandatory data and allows each transaction to be identified individually.
The most common and practical structure is a table with one row per transaction and one column for each required piece of data. The minimum columns are: registration number, purchase date, sale date, supplier's name, supplier's NIF, vehicle description (make, model, registration plate, VIN), purchase price, sale price, and margin.
Transactions must be recorded in chronological order of the sale date, which is when the VAT becomes chargeable. If a transaction is closed on 28 March, it goes into the first-quarter registry book and into form 303 for that quarter.
At the end of each quarter, the book must allow the direct calculation of the sum of the positive margins of the period, which is the total taxable base to which the 21% rate is applied to obtain the VAT payable in form 303. Negative margins (sales at a loss) are not added or subtracted: each REBU transaction is handled separately.
When to record each transaction
The transaction must be recorded at the moment the vehicle is transferred to the final buyer, which is when the VAT becomes chargeable. In practice, the correct moment is the day of signing the sales contract and delivering the vehicle.
Recording transactions late, for example at the end of the quarter to prepare form 303, is a practice that works in terms of tax results but creates risk in the event of an inspection: if the Tax Agency detects that the entries are not contemporary to the transactions, it can question the reliability of the book and request additional documentation for each transaction.
See also the accounting obligations and tax forms of a dealership.
The correct habit is to record each transaction on the same day or the day after the sale. With a management system that automates the registry, this work requires no additional time.
The REBU registry book in mixed operations: REBU and general regime
A dealership that operates under both the REBU and the general VAT regime (because it buys some cars from companies with a VAT invoice and resells them under the general scheme) must maintain separate records for each type of transaction.
Transactions under the general regime are recorded in the usual output VAT invoice book, with the VAT itemised. REBU transactions are recorded in the specific REBU registry book, without itemised VAT.
Read also special REBU cases: when it does not apply and how to manage them.
In the quarterly form 303, the two taxable bases are declared separately: the output VAT from the general scheme in the corresponding boxes, and the REBU taxable base in its specific box (box 25 of the current form 303). Mixing the two types of transaction in the same record generates declaration errors and makes justification difficult during an inspection.
How the book is used in the quarterly VAT return
At the close of each quarter, the process of preparing form 303 with the REBU registry book follows three steps.
First, add up all the positive margins from the REBU transactions of the quarter. This total is the REBU taxable base that goes into box 25 of form 303.
Second, apply the 21% rate to that taxable base to obtain the REBU tax amount. This amount is added to the output VAT from the general scheme (if there are transactions under that scheme) to obtain the total output VAT for the quarter.
Third, subtract the deductible input VAT (purchase invoices under the general scheme, business expenses with itemised VAT) to obtain the amount payable or to be offset.
Negative REBU margins (sales at a loss) are not included in the taxable base: they simply have a taxable base of zero. They cannot be used to offset positive margins from other transactions in the same quarter.
How long it must be kept for
The REBU registry book must be kept during the tax limitation period, which is four years from the submission of the last tax return that references it. In practice, as the book accumulates transactions from several financial years, it is advisable to keep the complete book for four years from the submission of form 303 for the last quarter of the last financial year included in it.
For high-value transactions or in sectors with high tax litigation, keeping the book and supporting documentation for ten years is a prudent practice that goes beyond the legal minimum but provides security against inspections of prior financial years.
Keeping the supporting documentation for each entry (purchase invoice or receipt, sales contract with the final customer) for the same period also greatly facilitates the defence in the event of an inspection.
See also which documents to keep in transactions between professionals.
Tools to keep the registry book without manual work
The REBU registry book can be kept on paper, in a spreadsheet, or using specific management software. Each option has advantages and disadvantages.
The paper book meets the legal obligation but is slow to prepare, difficult to consult, and easy to lose. It only makes sense for businesses with very few transactions per month.
The spreadsheet is more practical than paper and allows for the automatic calculation of quarterly totals if well designed. The risk is manual data entry, which generates errors, and the lack of connection with the rest of the business management system.
Specific management software for dealerships that automatically generates the REBU registry book from the transactions recorded in the platform is the most efficient option. The data is entered once (when registering the purchase and sale of the vehicle) and the system automatically generates the entry in the registry book with all the required fields.
Read which software for dealerships includes the management of the REBU registry book.
Dealcar and the automated REBU registry book
Dealcar automatically generates the REBU registry book from the transactions recorded on the platform. Every time a vehicle purchase is registered with its data and the sale to the final customer with the sale price, the system updates the registry book with the complete entry: supplier details, vehicle description, purchase price, sale price, and calculated margin.
At the end of each quarter, the registry book is ready for the administrative agency without additional manual work.
If you want to see how it works, check out dealcar.io/verifactu-para-concesionarios or request a demo at dealcar.io.
Frequently asked questions
Does the REBU registry book have to be numbered or have an official format?
There is no mandatory official format. The VAT Regulations only require that it contain the established minimum data and that it allow each transaction to be identified individually. It can be a digital document, a spreadsheet, or a physical book. What is important is that the data is complete and organised in chronological order of the sale date.
What happens if during an inspection some information is missing from entries in the book?
The Tax Agency may require additional documentation to complete incomplete entries. If this documentation cannot be provided, it can reject the application of the REBU to the affected transactions and recalculate the VAT under the general scheme. The level of consequences depends on the severity and volume of the omissions.
Can the registry book be corrected if an error is detected?
Yes. Corrections must be made in such a way that the original error is visible (do not erase, but add a correction entry with the date of the correction). On paper, the incorrect data is crossed out and the correct data is written. In digital systems, a correction note linked to the original entry is added. The correction must be accompanied by the documentation justifying the change.
Is the REBU registry book the same for sole traders and companies?
The mandatory content is the same for both legal forms. The difference is that in a company, the REBU registry book is part of a broader accounting system that includes double-entry bookkeeping, whereas for a sole trader, it is one of the registry books that replace formal accounting.
