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The short answer
Spain gives a deduction for international double taxation: you declare the Nigerian income in your Renta and subtract the Nigerian tax paid on it, up to the Spanish tax on that same income. The Spain–Nigeria treaty sets this cap. Keep withholding tax receipts, bank statements and contracts, because the AEAT can ask you to prove both the income and the tax.
What the deduction is
Spanish residents are taxed on their income wherever it arises, so Nigerian rent, interest, dividends or fees can be taxed first in Nigeria and then in Spain. Spain relieves this through the deducción por doble imposición internacional, which the Agencia Tributaria's Manual práctico de Renta 2025 lists among the deductions for income obtained and taxed abroad. It comes off your Spanish tax bill at the end of the Renta calculation; it does not reduce the income you declare.
How much you can claim
The Spain–Nigeria treaty (in force since 5 June 2015) sets the frame in Article 24. The country of residence allows a deduction equal to the income tax paid in the other country, but the deduction may not exceed the part of its own tax that relates to the income taxable in the other country. In practice that means the credit is the lower of:
- the Nigerian tax actually paid on that income; and
- the Spanish tax attributable to that same income.
Two further limits matter. Tax Nigeria charged above a treaty cap (for example, more than 7.5% on interest) may not be accepted as creditable in Spain, so it is better to claim the treaty rate in Nigeria at source. And the protocol to the treaty contains a remittance clause: where relief depends on income being remitted, the claim is allowed if the income reaches Spain within six years of payment (four years for Nigeria), on the taxpayer's request.
Worked example (illustrative figures)
Chidi lives in Seville and has two Nigerian income items for the year, converted to euros.
| Lagos rent | Nigerian interest | |
|---|---|---|
| Income declared in Spain | €3,000 | €1,000 |
| Nigerian tax paid | €300 (10% withheld) | €75 (7.5% treaty rate) |
| Spanish tax attributable (example) | €570 | €60 |
| Credit allowed (lower figure) | €300 | €60 |
| Nigerian tax not relieved | €0 | €15 |
Chidi's total credit is €360 (€300 + €60). The rent credit is limited by the Nigerian tax; the interest credit is limited by the Spanish tax, so €15 of Nigerian tax on interest goes unrelieved. The Spanish tax figures are examples only; your own depends on your other income and the rates for the year.
Which Nigerian taxes count
The treaty covers Nigerian Personal Income Tax, Companies Income Tax, Petroleum Profits Tax, Capital Gains Tax and Education Tax, and later taxes that are identical or substantially similar (Article 2). For a typical Nigerian in Spain the relevant items are withholding on rent, interest, dividends and fees, personal income tax assessed by NRS, and capital gains tax on selling land or shares. Charges that are not taxes on income, such as Lagos Land Use Charge, bank charges or stamp duties, are not income tax paid and should not be put into the deduction.
Timing
Match the Nigerian tax to the Spanish year in which you declare the income. Spain's tax year is the calendar year, while a Nigerian tenancy may run from March to February, so split the rent and the withholding by the months that fall in each calendar year, and keep the workings with your receipts.
The proof you need
The AEAT can ask you to prove both the foreign income and the tax. Build the file before you file.
- Withholding tax receipts or credit notes. Nigeria's 2024 Withholding Tax Regulations (as summarised by Mondaq) say the person deducting must issue a receipt showing name, address, tax ID, nature of the payment, gross amount, tax deducted and month. Ask your tenant, bank or client for them every year.
- Bank statements showing the net amount received.
- Contracts: tenancy agreement, loan or deposit terms, invoices to Nigerian clients.
- Nigerian returns and assessments where you file with NRS, plus evidence of payment.
- Exchange rate workings for every conversion to euros.
- Translations if the office asks for documents in Spanish.
Withholding receipts are the most common gap. Many Nigerian tenants and agents deduct and pay but never send a receipt. Without one, the AEAT may not accept that tax was paid. Agree in the tenancy that the tenant sends the receipt with each payment.
Steps
- Declare each Nigerian income item gross, in euros, in the right section of Modelo 100 (see filing the Renta with Nigerian income).
- Total the Nigerian tax paid on each item, using receipts.
- Fill in the double taxation deduction with the foreign income and foreign tax figures; Renta WEB calculates the cap.
- Keep the file of evidence for as long as the AEAT can review the year.
Where Pryme fits
Clear records make the credit easier to defend. Pryme's verifiable receipts and statements, made with VerifyDoc.ai, let anyone check a statement is genuine and unaltered. Your naira income can stay in naira until you convert with Swap, where the app shows the rate and the fee before you approve.
Questions people ask
How do I claim Nigerian tax paid in my Spanish Renta?
Declare the Nigerian income gross and fill in the deduction for international double taxation with the foreign tax paid. The credit is capped at the Spanish tax on that income.
My tenant deducted 10% but gave me no receipt. Can I still claim?
You may struggle to prove it. Ask the tenant for the withholding receipt; the 2024 Regulations require the deductor to issue one.
Can I claim more than the Spanish tax on the income?
No. Any Nigerian tax above the Spanish tax on that income is not relieved in Spain.
Nigeria charged 10% on my interest. Can I credit all of it?
The treaty caps Nigerian tax on interest at 7.5%, and Spain may refuse to credit the excess. Claim the treaty rate in Nigeria at source where you can.
Sources
- Spain–Nigeria Convention for the avoidance of double taxation and Protocol (English text published by the Ministerio de Hacienda) · accessed Oct 2026
- Convenio entre el Reino de España y la República Federal de Nigeria para evitar la doble imposición, y Protocolo (BOE 13 Apr 2015; Ministerio de Hacienda copy, Spanish) · accessed Oct 2026
- Agencia Tributaria: Manual práctico de Renta 2025, Parte 1 (index) · accessed Oct 2026
- Mondaq: An overview of the Nigerian Withholding Tax Regulations of 2024 (Jul 2024) · accessed Oct 2026
- PwC Worldwide Tax Summaries: Nigeria, corporate withholding taxes (reviewed 29 May 2026) · accessed Oct 2026
This article is general information, not financial, legal or tax advice. Products described are provided under the terms on this site and are subject to regulation and eligibility.