File the Modelo 303 VAT return
Output VAT minus input VAT, every quarter. Cofactu pre-fills it from your invoices and expenses: you check the boxes and file.
- Category
- Tax
- Level
- Intermediate
- Time
- ≈ 15 min
- Steps
- 5
- Updated
- July 2026
Before you start.
What you are about to solve.
The Modelo 303 is the quarterly VAT self-assessment in Spain: you declare the VAT you charged on your invoices (output VAT, IVA devengado) and subtract the VAT you paid on your deductible expenses (input VAT, IVA soportado). The result is payable, to offset or refundable. If you invoice with Cofactu, that calculation is already done from your VAT book (libro registro de IVA).
The difference between understanding the 303 and filing it properly lies in the boxes: what goes in each, which expenses are deductible and how to treat special operations (intra-community, reverse charge, equivalence surcharge). Cofactu maps your records to the boxes of the current form and lets you review before filing.
This guide takes you from having the quarter invoiced to generating the 303 ready for the AEAT (Spanish Tax Agency). For the regulatory detail of each box, complement it with the Modelo 303 page.
Do it in order.
Open only the step you are on.
5 steps to review, issue and leave the document ready, without reading a whole guide at once.
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Close the quarter
Step 01: Close the quarter
Make sure all the quarter's issued invoices are recorded and that you have entered the expenses with input VAT you want to deduct. The 303 is calculated on what is in the VAT book at the date, so an expense that is not entered is not deducted.
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Open the 303 draft
Step 02: Open the 303 draft
In Returns → 303, choose the quarter. Cofactu generates the draft mapping your VAT book to the boxes: output VAT by rate (21%, 10%, 4%) goes to the general regime, deductible input VAT to the deduction boxes, and it calculates the settlement result. You do not start from a blank sheet.
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Check the key boxes
Step 03: Check the key boxes
Check the boxes where adjustments usually occur: base and output VAT for each rate, input VAT on domestic operations, intra-community acquisitions and imports if there are any, and the result in box 71. If something does not match what you expected, it is almost always a wrongly classified invoice or expense that you can correct and recalculate.
- Boxes 01-09: output VAT by rate in the general regime.
- Boxes 28-30: deductible input VAT on domestic operations.
- Box 71: settlement result (payable / to offset / refundable).
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Check the deadline
Step 04: Check the deadline
The 303 is filed in the month after the end of the quarter: until 20 April (Q1), 20 July (Q2), 20 October (Q3) and 30 January (Q4). If you set up direct debit for payment, the deadline usually closes a few days earlier. Cofactu warns you in advance of each due date so you do not miss it.
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Generate the file or file directly
Step 05: Generate the file or file directly
With the draft reviewed, generate the 303 file to upload it to the AEAT portal, or file it directly if you have the certificate configured. Cofactu keeps a copy of what was filed with its date, so the quarter stays archived and traceable.
When you finish you will have the quarter's Modelo 303 calculated from your real data, with the boxes reviewed and the file or filing ready for the AEAT, and the balance to offset carried forward if applicable.
The questions that come up
when you put it into practice.
Does Cofactu calculate the 303 by itself or do I enter data by hand?
It calculates it from your VAT book: issued invoices provide the output VAT and expenses the deductible input VAT. You review and adjust special cases, but you do not start from zero or add up invoices by hand.
Which expenses can I deduct in the 303?
The VAT on expenses linked to your business activity, with a full invoice in your name. The VAT on personal expenses, on simplified tickets without your details or on categories with a legal restriction is not deductible. Cofactu flags the non-deductible ones, but you decide whether they are linked to the activity.
What if the result is negative (refundable or to offset)?
If input VAT exceeds output VAT, the result is to offset (carried forward to the next quarter) or refundable (only in Q4 or under the monthly refund regime). Cofactu manages the carry-forward of the balance automatically.
Does the 303 have anything to do with VeriFactu?
They are different but connected: VeriFactu regulates how invoices are issued and recorded; the 303 is the VAT return fed by those invoices. When you issue with Cofactu, your invoices already feed the VAT book that then fills in the 303.
Continue from here.
Without losing context.
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