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The short answer
In London you can sell US dollar notes to a bureau de change or a Post Office branch that handles foreign currency; some banks also buy notes from their own customers. Each pays its own "we buy" rate, which sits below the mid-market rate, and the Post Office says its rates vary by branch. Compare the pounds you will actually receive, not the headline rate or a "no commission" sign.
Where dollar notes can be sold
Dollars are among the easiest currencies to sell in London, unlike naira. The options fall into three groups, and they price the same notes differently.
| Option | How it works | What to watch |
|---|---|---|
| Post Office branch | Take notes to a branch that deals in foreign currency; the Post Office buyback page lists USD | Rates vary by branch; the online calculator is guidance only |
| High-street or airport bureau | Walk in, hand over notes, receive pounds | The buy rate and any fee; airport counters often price differently from city ones |
| Your own bank | Some banks buy foreign notes from customers in branch | Ask first: not every branch handles foreign cash |
| Paying in to a USD account | If you hold a dollar account that accepts cash | Cash handling charges; the money is still in dollars |
Any business offering currency exchange in the UK must be registered with HMRC as a money service business under the Money Laundering Regulations, and GOV.UK publishes that requirement. If a counter cannot show its registration, or an individual offers to swap notes privately, walk away.
How the Post Office buyback works
The Post Office's currency buyback page says you take leftover foreign cash to a branch that handles foreign currency. Its calculator gives a rate "for guidance only", and the page adds that "rates may vary by branch". Larger branches do not need your original purchase receipt; smaller ones do. The page shows no buyback fee and no limit, but its terms are linked rather than printed, so ask at the counter before you hand notes over.
The Post Office refund promise is a separate thing: it covers currency bought from the Post Office for a holiday that was cancelled, within 28 days of purchase. It does not set the price for dollars you bring from Nigeria.
Comparing rates: the only number that matters
Every buyer quotes a rate at which it buys dollars from you. The mid-market rate is the midpoint between buying and selling in the wholesale market, and the Bank of England publishes a daily spot rate you can use as a reference. The gap between that reference and the counter's rate is the buyer's margin. A "0% commission" sign can sit alongside a wide margin.
Worked example: US$1,000 in notes
Example only, with invented counter rates. Suppose the Bank of England reference that week is US$1.3363 to the pound, which values US$1,000 at about £748.
| Counter | Quoted buy rate (US$ per £) | Fee | You receive |
|---|---|---|---|
| A | 1.42 | None | £704.23 |
| B | 1.39 | £4 | £715.42 |
| C | 1.48 | None | £675.68 |
Counter B charges a fee yet pays the most, because its rate is closer to the reference. Against £748, A keeps about £44, B about £33 and C about £72. Ask each counter: "How many pounds will I get for exactly this amount?"
Practical points for notes from Nigeria
- Bring ID. Bureaux carry out checks under money laundering rules, and larger amounts attract more questions about where the money came from.
- Keep the record of where the dollars came from: a Nigerian domiciliary withdrawal slip, or the declaration if you carried a large sum in. Our guide to bringing cash from Nigeria into the UK covers the £10,000 rule.
- Check the notes before you travel. Buyers inspect notes and may refuse damaged ones; ask about older series too, as acceptance is set by each buyer.
- Count the timing. Selling at an airport on arrival is convenient but rarely the best rate; a city branch a few days later may pay more.
Larger amounts: questions to expect
Selling a few hundred dollars after a holiday is routine. Selling several thousand in notes is not, and bureaux are required to ask more as amounts grow. Expect to be asked where the dollars came from, why you are holding cash, and possibly for proof of address. That is the counter following its own anti-money laundering duties, not an accusation.
- Bring the paper trail: a Nigerian bank statement showing the withdrawal, an exchange receipt, or a sale agreement if the dollars came from selling something.
- If you carried £10,000 or more in cash into the UK, bring the customs declaration reference too.
- Consider splitting the sale only for practical reasons, such as a counter's cash on hand. Splitting to stay under a checking threshold is the kind of pattern that raises concern.
- Once the pounds are in your UK account, keep the bureau receipt with the statement entry. Your bank may ask about a large cash deposit later.
When selling is not the best move
If you will need dollars again, for a trip, US fees or a relative's school costs, converting twice costs two margins. Some UK banks offer dollar currency accounts; our guide to holding dollars in a UK account explains the options and how deposit protection differs between banks and e-money firms. For larger sums that are already in a Nigerian dollar account, a transfer to a UK account usually leaves a cleaner record than flying with notes; see wiring from a domiciliary account to the UK.
Where Pryme fits
Pryme does not exchange cash notes. If the dollars you are carrying started in an account, a Pryme multicurrency account can hold USD and GBP side by side, and Swap converts when you choose, with the rate and fee shown before you approve. Outside Nigeria, Pryme's services are provided through regulated partners.
Questions people ask
Where can I change dollars to pounds in London?
At Post Office branches that handle foreign currency, at bureaux de change, and at some banks for their own customers. Each pays a different buy rate, so compare the pounds you will receive.
Does the Post Office buy back US dollars?
Yes. Its buyback page lists USD and says you take the notes to a branch that deals in foreign currency. It says rates may vary by branch and the online rate is for guidance only.
Do I need a receipt to sell dollars at the Post Office?
The Post Office says larger branches do not need the original purchase receipt but smaller branches do.
How do I know if a bureau is offering a fair rate?
Compare its buy rate with the Bank of England daily spot rate for the same day. The difference, plus any fee, is what the sale costs you.
Sources
- Post Office: Currency buyback, sell unused currency · accessed Oct 2026
- GOV.UK: Money Laundering Regulations, money service business registration · accessed Oct 2026
- Bank of England: Daily spot exchange rates against sterling · accessed Oct 2026
- GOV.UK: Take cash in and out of the UK (Great Britain) · 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.