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The short answer
Yes. If you are tax resident in Spain, interest from Nigerian Treasury bills is savings income on your Renta return, taxed at 19% on the first €6,000 and up to 30% above €300,000. Nigeria now withholds tax on T-bill interest, and Spain lets you deduct the Nigerian tax up to the lower of that tax and the Spanish average rate on the interest.
Treasury bills are popular with Nigerians abroad because the naira yields are high and the issuer is the Federal Government. For a Spanish tax resident there are two tax systems involved: Nigeria's, which now deducts tax at source, and Spain's, which taxes your worldwide income. Getting both right means you pay once, not twice.
The Nigerian side: withholding tax now applies
In late 2025 the Nigerian tax authority directed financial institutions to deduct withholding tax on interest from short-term securities. KPMG's December 2025 summary says the tax is deducted on the payment date and remitted by the 21st, that deductions which are not final are creditable, and that FGN bond interest remains exempt. Treasury bills are short-term securities, so expect a deduction on the discount you earn. PwC's Nigeria summary lists 10% withholding on interest, and its treaty table shows 7.5% for Spain. To claim the treaty rate, the FIRS circular of May 2022 requires a certificate of residence endorsed by your home tax authority, which in Spain is the AEAT's certificado de residencia fiscal. Ask your bank or dealer what it deducts.
Claiming the treaty rate in Nigeria
The FIRS circular (the authority now operates as the Nigeria Revenue Service) sets out what a non-resident submits to get a treaty rate on interest:
- A certificate of residence endorsed by the tax authority of the country where you live.
- A letter to the Executive Chairman, for the attention of the tax policy and advisory department.
- Evidence of the income, such as the investment documents.
- A declaration that you are the beneficial owner and have no permanent establishment in Nigeria.
The approval is passed to the bank or dealer that deducts the tax. The circular says the treaty rate is a cap that applies only where the domestic rate is higher, and it is silent on refunds of tax already deducted. For a small holding, the paperwork may cost more time than the 2.5-point difference saves; as the example below shows, Spain's credit means the total tax is often the same either way.
The Spanish side: savings income
PwC's Spain summary (reviewed June 2026) says residents are "generally subject to PIT on their worldwide income", and lists interest and other income from lending your capital among savings income. The savings scale is:
| Savings base | Rate |
|---|---|
| First €6,000 | 19% |
| €6,000 to €50,000 | 21% |
| €50,000 to €200,000 | 23% |
| €200,000 to €300,000 | 27% |
| Over €300,000 | 30% |
T-bill interest is the difference between what you paid and what you received at maturity. You report it in euros, so it must be converted; ask your gestor which exchange rates the AEAT expects for the purchase and maturity dates.
How the credit for Nigerian tax works
PwC describes Spain's deduction for international double taxation as the lesser of the foreign tax actually paid and the result of applying your average effective Spanish rate to the foreign income. Where a treaty applies, its terms guide the calculation; PwC lists Nigeria among Spain's treaty partners.
A worked example
Example only, with round numbers. Emeka in Seville earns interest on a Nigerian T-bill worth €1,500 after conversion. Nigeria withheld 10%, so €150. Assume his Spanish average effective rate on savings income is 19%.
- Spanish tax on the interest: €1,500 x 19% = €285.
- Credit: the lower of the Nigerian tax (€150) and €285, so €150.
- Spanish tax still to pay on this interest: €285 - €150 = €135.
- Total tax on the interest across both countries: €150 + €135 = €285, the Spanish amount, not €435.
If the 7.5% treaty rate had been applied in Nigeria, he would have paid €112.50 there and €172.50 in Spain: the same €285 overall, with more of it in Spain.
The currency point people miss
Spain taxes the interest, but your real return is in euros after the naira moves. If the naira falls against the euro while the bill runs, the euro value of your principal at maturity is lower than when you bought. Whether that loss can be set against the interest for Spanish tax is a technical point; ask an asesor. Our guide to saving in naira or euros shows how depreciation eats into yield.
Reporting checklist
- Keep the contract note showing purchase price, face value and maturity date.
- Keep the bank statement showing the maturity payment and any tax deducted.
- Ask for a withholding tax credit note or statement.
- If your Nigerian securities and accounts pass the limit, file Modelo 720 as well.
- See claiming the foreign tax credit in Spain for the Renta boxes.
How to buy the bills is covered in buying Nigerian T-bills from Spain and, for the Nigerian mechanics, how to buy Treasury bills in Nigeria.
Where Pryme fits
Verifiable statements from VerifyDoc.ai give your gestor a record of maturity payments that can be checked, and a Pryme account holds NGN and EUR so proceeds can stay in naira or be converted with Swap when you choose.
This is general information, not tax advice.
Questions people ask
Do I pay tax in Spain on Nigerian Treasury bills?
Yes, if you are tax resident in Spain. The interest is savings income, taxed at 19% to 30%.
Are Nigerian T-bills tax-free?
Not any more for withholding: Nigeria directed deduction of withholding tax on short-term securities, including T-bills, from late 2025. FGN bond interest stays exempt.
Can I offset Nigerian withholding tax in Spain?
Yes, up to the lower of the Nigerian tax paid and the Spanish average rate applied to that income.
What rate does the Spain-Nigeria treaty set on interest?
PwC's Nigeria table lists 7.5% for Spain. Claiming it needs an AEAT certificate of residence.
Sources
- PwC Worldwide Tax Summaries: Spain, taxes on personal income (reviewed 30 Jun 2026) · accessed Oct 2026
- PwC Worldwide Tax Summaries: Spain, foreign tax relief and tax treaties (reviewed 30 Jun 2026) · accessed Oct 2026
- KPMG TaxNewsFlash: Nigeria guidance on withholding tax on interest from short-term securities (4 Dec 2025) · accessed Oct 2026
- PwC Worldwide Tax Summaries: Nigeria, withholding taxes (reviewed 29 May 2026) · accessed Oct 2026
- FIRS Information Circular 2022/15 on claiming tax treaty benefits (11 May 2022, hosted by KPMG) · 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.