Cost basis and exchange rates for investments bought before you moved

Key rules

• No step-up: Moving to Spain does not revalue your investments; your original cost and purchase date remain your basis.
• Proof: You must prove your cost and date, so keep broker statements, contract notes and bank payment records.
• Missing records: Ask your broker for duplicate records before you sell.
• Foreign tax: Tax you paid abroad on the same gain may be relieved under a treaty or a foreign tax credit.

Your original cost and date stay your basis

Becoming a Spanish tax resident does not reset the value of what you own. There is no "arrival step-up". If you bought shares or funds abroad, your basis is what you originally paid, on the date you originally paid it.

When you sell, Spain taxes the sale price minus that original cost. That includes any gain the investment built up before you moved. Example: you bought shares for 10,000 before arriving, they were worth 15,000 on arrival, and you sell them for 15,000 after arriving. Your taxable gain is 5,000, not zero.

If you already paid tax abroad on the same gain, you may be able to reduce the Spanish tax. This can work through a tax treaty between Spain and the other country, or through a credit for foreign tax paid. Keep proof of what you paid abroad.

You must be able to prove it

The burden of proof is on you. If you cannot show what you paid and when, the tax office can challenge your figures. Good evidence includes:

• Broker statements and transaction confirmations (contract notes) showing date, quantity, price and fees.
• Annual statements from your broker or bank showing what you held and when.
• Bank records of the payment for each purchase.
• For funds, the subscription confirmations.

The documents list below has the full set. Collect these early, ideally before you move, while your foreign accounts are easy to reach.

If records are missing

Ask your broker for duplicates. Many can produce historical reports covering past purchases. Do this before you sell, not after, because you will need the figures when you file.

Keep everything for at least 4 years after the filing period in which you use it. For assets you still hold, keep the records for as long as you own them, because you must prove the cost on the day you sell. If the Spanish tax agency asks, you may need to translate foreign-language documents.

What counts in your arrival year

Residency is decided for the whole calendar year. If you spend more than 183 days in Spain, or your main economic interests are there, you are resident for the full year, with no split period. Spanish residents are taxed on worldwide income, so income and gains you made abroad earlier in your arrival year can fall into your Spanish return.

Two things can change this result. A tax treaty may decide which country you belong to if both claim you. And if you qualify for the Beckham regime, you are taxed as a non-resident on Spanish income only, and foreign investment income is largely outside Spanish tax. If either may apply to you, get advice from a tax adviser before you sell.

The timeline below shows the order to do these steps in.

Timeline and deadlines

• Request duplicate records from your broker if any are missing: before you sell or file your first Spanish return

• Check whether you pass the 183-day test, which makes you resident for the whole arrival year: during the year you arrive, and again at year end

Documents you need

• Broker statements and transaction confirmations (contract notes) showing the date, quantity, price and fees of each purchase. Your broker issues them.

• Annual account statements from your broker or bank, which back up what you held and when.

• Bank records showing the payment you made for each purchase. Your bank issues them.

• For funds, the subscription confirmations from the fund manager or platform.

• A translation of any foreign-language document, needed only if the Spanish tax agency asks for it.

Frequently asked questions

Do gains made before I moved count when I sell after arriving?

Yes, a gain that built up before you moved counts when you sell after becoming Spanish tax resident, because your original cost and date carry over. The gain is the sale price minus what you originally paid. Tax paid abroad on the same gain may be relieved under a tax treaty or a foreign tax credit.

What if I no longer have the records of what I paid?

Ask your broker for duplicate statements, because it can usually provide historical reports. Bank records of the payment and, for funds, subscription confirmations also help. The burden of proving cost and date is on you, so gather them before you sell.

Are income and gains from before my move taxed in my arrival year?

They can be, if you count as Spanish resident for that year. Someone who becomes resident through the 183-day test is generally treated as resident for the whole year, with no split period. Foreign tax paid on that income may be credited, and the special regime for inbound workers (the Beckham regime) can change the result.