Currency Conversion Costs: 0.25% to 0.99% on UK Platforms

Key takeaways

• Converting £1,000 into dollars costs £2.50 to £9.90 across seven UK platforms priced on 8 August 2026 — the same piece of plumbing, quoted 3.96 times apart.
• Buying a US-listed ETF with £1,000 a month costs £118.80 a year in currency charges at Hargreaves Lansdown and £30.00 at interactive investor's Premium plan.
• Tiered rate cards reset on every conversion. At £3,000 a month, twelve conversions cost £356.40 at Hargreaves Lansdown against £196.00 for one £36,000 conversion.
• Every UK charge is quoted over a rate nobody publishes. The Bank of England's own daily spot series moved 1.59% between 1 and 16 July 2026.
• IG's multi-currency route drops the 0.49% fee but adds a $15 minimum commission, worth £11.14, so it only pays above roughly £2,270 a trade.

The answer first: 0.25% to 0.99% of everything you convert

You want a US-listed ETF. Your money is in pounds, the fund trades in dollars, and somewhere in between a platform takes a cut. How big is it?

On seven UK tariff pages retrieved on 8 August 2026, the charge on a £1,000 conversion runs from 0.25% to 0.99%. That's £2.50 at one end and £9.90 at the other, for an identical instruction to a market maker. The gap is a factor of 3.96, and it's larger than the gap between most global tracker funds.

The number that matters, though, isn't the headline rate. It's what the charge does to a repeated purchase. Convert £1,000 a month for a year and the annual bill runs from £30.00 to £118.80 — a spread of £88.80 on £12,000 invested. This piece covers only the currency layer. The custody and dealing charges around it are set out in the comparison of flat and percentage platform fees, and the charges inside the fund in the anatomy of a fund's total cost.

What seven UK platforms charge to turn pounds into dollars

Here's what the published rate cards said on 8 August 2026. Every figure is quoted as a percentage of the amount converted, and every one of them sits on top of a wholesale rate rather than replacing it.

Two features of that table do more work than the ranking. The first is the tiering, which decides how much a monthly buyer pays. The second is IG's asterisk. IG says the 0.49% rate "is offered at IG's discretion and will apply for a minimum period until 4 September 2026" — a published price with an expiry date on it.

On £1,000 a month, the annual charge runs from £30.00 to £118.80

Take one realistic pattern. You pay £1,000 into a US-listed ETF on the same day each month, and each purchase needs its own conversion. Nothing here is a one-off cost, because you keep buying.

The chart plots the annual result. At Hargreaves Lansdown and Freetrade's Basic plan the charge is £118.80 a year. At AJ Bell, Fidelity and interactive investor's Core plan it's £90.00. Freetrade Standard comes to £70.80, IG to £58.80, Freetrade Plus to £46.80, and interactive investor's Premium plan to £30.00.

That's £88.80 a year between the ends of the range, on £12,000 invested. Set against a global tracker's ongoing charge, it isn't trivial, and it doesn't shrink as the portfolio grows — it scales with what you pay in, not with what you hold. Someone contributing the same £1,000 a month for a decade converts £120,000, and the currency charge is levied on every pound of it.

The tiers reset on every conversion, so a monthly buyer never reaches the cheap band

This is the part the rate cards don't spell out. Hargreaves Lansdown's cheapest band, 0.20%, applies to deal value over £25,000. Its note explains the mechanism: "The FX charge is applied to each deal value band. For example, on a £15,000 deal, the charge will be 0.99% of the first £10,000 and 0.50% of the next £5,000."

Per deal. So twelve conversions of £1,000 each sit entirely inside the top band. You pay 0.99% on all £12,000, and you never see 0.50%, let alone 0.20%. One conversion of £12,000 costs £109.00 instead — 0.99% on the first £10,000 and 0.50% on the remaining £2,000, an effective 0.91%. The saving is £9.80 a year, and at AJ Bell the equivalent saving is £5.00. Small enough that nobody would restructure their investing around it.

Now run the same choice at £3,000 a month. Twelve conversions cost £356.40 at Hargreaves Lansdown. One conversion of £36,000 costs £196.00 — 0.99% on the first £10,000, 0.50% on the next £15,000, and 0.20% on the last £11,000, an effective 0.54%. Splitting it into twelve monthly instalments costs £160.40 a year. At AJ Bell the same comparison is £270.00 against £165.00, a difference of £105.00.

The quoted headline rate and the rate you pay part company as the sums get bigger, and they part company in the direction that costs the regular buyer more. On a flat card — interactive investor, Freetrade, IG — none of this applies, because there's nothing to reach. A flat 0.75% is 0.75% whatever the size of the conversion.

The rate you convert at is not a rate you can look up

Every one of these charges is expressed as a margin over a benchmark. Hargreaves Lansdown converts "at the prevailing interbank exchange rate, by a UK-based market maker". AJ Bell's charge "is based on the sterling consideration after conversion to/from the local currency at the prevailing spot FX rate". interactive investor says: "When we convert your currency, we use the current exchange rate (or 'spot rate')."

None of those is a published number. There's no tape of interbank quotes a retail client can consult, and the reference rates that do exist are explicit that they aren't transaction prices. The European Central Bank publishes its euro reference rates from a concertation procedure at around 14:10 CET, and states flatly: "The reference rates are published for information purposes only. Using the rates for transaction purposes is strongly discouraged." The Bank of England is blunter still about its own daily spot series: "the exchange rates are not official rates and are no more authoritative than that of any commercial bank operating in the London foreign exchange market."

So you can't check the margin after the fact by comparing your contract note to a published rate, because the benchmark moves faster than the publication does. On the Bank of England's series, sterling bought $1.3278 on 1 July 2026 and $1.3489 on 16 July 2026 — a 1.59% move in eleven trading days, larger than the entire spread between the cheapest and dearest UK platform charge. A rate fixed at 16:00 is not the rate at your 11am trade.

That is what "0.99% over interbank" really tells you: the size of the margin, and nothing about the price it was added to. AJ Bell adds one more line most cards omit — "We may share a proportion of this charge with our service provider" — which says the charge isn't purely a pass-through of what the conversion cost.

Where the charge lands: the sterling consideration, both legs, and the income

Three details decide how often you meet the charge.

It's levied on the value of the conversion, not on your profit. AJ Bell states the base plainly: the charge "is based on the sterling consideration after conversion". Fidelity's own worked example shows it landing on the whole ticket — a £15,000 international share purchase carries £75 at 0.75%, £25 at 0.50% and a £7.50 dealing charge, £107.50 in total, of which the dealing commission is the small part.

It applies on the way out as well as the way in, because selling a dollar holding converts dollars back to pounds. And it applies to income. Hargreaves Lansdown converts foreign dividends automatically, at "the prevailing interbank exchange rate, to which we add an additional spread of 1% as our charge". AJ Bell charges 0.5% on dividends and corporate action payments. On an accumulating fund that never distributes, this leg doesn't arise; on a portfolio of individual US shares it arises every quarter, and there's no opt-out at Hargreaves Lansdown.

A multi-currency account moves the charge rather than removing it

The obvious answer is to hold dollars. Convert once, buy repeatedly, let dividends stay where they land. Two of the platforms here publish terms for that, and neither makes it the free lunch it sounds like.

interactive investor says "you can hold multiple currencies in your ii Personal Pension (SIPP) and Trading Account", and that the charge applies "either as part of a trade or a stand-alone transaction". Same rate either way. On the Core plan's flat 0.75%, converting £12,000 in one go costs exactly what twelve £1,000 conversions cost — £90.00. Holding dollars there saves nothing on the way in. What it saves is the second conversion: a dollar dividend can be left in dollars and reinvested without paying again.

IG goes further and drops the fee entirely. "Switching to manual currency conversion allows you to deposit multiple currencies and trade in those currencies without FX fees. However, you'll no longer qualify for commission-free trading." The replacement commission on US shares is 3¢ a share with a $15 minimum — £11.14 at the 6 August 2026 spot rate of $1.3466. Against 0.49% on a £1,000 purchase, which is £4.90, the multi-currency route costs more than twice as much. It only breaks even at roughly £2,270 a trade, and that's before you account for getting dollars into the account in the first place, which is itself a conversion someone has to price.

So the multi-currency account pays where the trades are large, the holding pays dollar income, or the money would otherwise be round-tripped. On a £1,000 monthly purchase it does very little, and at IG it costs more.

Two brokers price the same service as a commission instead of a margin

There's a structurally different way to charge for this, and Interactive Brokers uses it. Its spot currency commission is 0.20 of a basis point of trade value, with a minimum of USD 2.00 an order. On a £1,000 conversion the percentage comes to about 2p, so the minimum does all the work: £1.49 at the 6 August rate, against £9.90 at Hargreaves Lansdown. Its automatic conversion service is priced differently again, at 0.03% added to or subtracted from the rate.

The firm is explicit about why it splits the two: "IBKR passes through the prices that it receives and charges a separate low commission. We do this in the interest of providing a transparent pricing structure instead of marking up our quotes and charging nothing in commissions as is the practice with many currency brokers."

The distinction has a regulatory shadow. The FCA's list of costs a firm must aggregate and disclose, at COBS 6 Annex 7R, names both forms in the same line: "mark ups (embedded in the transaction price), stamp duty, transactions tax and foreign exchange costs". A margin folded into the rate is a disclosable cost, not a feature of the rate. Whether a percentage on a tariff page discharges that in a way a reader can act on is a fair question, and one the tariff pages don't answer.

The case for ignoring all of this

The strongest objection is that these are small numbers dressed up as a scandal, and it deserves a proper hearing.

Start with the amount. £88.80 a year separates the dearest platform from the cheapest on a £12,000 annual contribution. A single bad month in equities moves the same portfolio by multiples of that, and nobody rearranges a portfolio around a figure that size. The charge is also avoidable in a way that costs nothing. Fidelity says its charge is "applied when dealing in offshore funds that are not in sterling" and "applied when dealing in international shares" — so a sterling-quoted, sterling-settled fund holding US assets triggers no conversion on your side at all. The currency exposure is identical; the retail margin isn't paid. Anyone holding a UK-domiciled global tracker in pounds has already sidestepped every number above.

Second, the comparison flatters the cheap platforms by looking at one charge. interactive investor's 0.25% comes on a £39.99 monthly plan, and Freetrade's 0.39% on a £9.99 one. Reading the FX column alone gets the ranking wrong, which is the whole argument for counting custody, dealing and withholding tax alongside conversion rather than in isolation.

Where the objection weakens is repetition. A one-off 0.99% on a lump sum genuinely is a rounding error over a long holding period. The monthly buyer doesn't pay it once. They pay it 12 times a year, on new money, at the top tier, with no path to the cheaper bands, and the tier arithmetic above shows the penalty rising with contribution size rather than falling.

What these tariff pages cannot tell you

The figures here are published prices, retrieved on 8 August 2026. They are not measured execution costs, and the difference matters.

Nothing in this piece observes the wholesale rate any of these platforms actually received. That's the central limit: the margin is disclosed, the base isn't, so a comparison of margins is a comparison of the visible half of the price. Two platforms quoting 0.75% could deliver different results if one converts at a keener wholesale rate than the other, and there is no public dataset that would settle it.

The prices also move. IG's 0.49% carries an explicit discretionary expiry of 4 September 2026. Rate cards get restated without notice, and the sample here is seven providers, not the whole UK market. Trading 212's and Vanguard's pages both refused automated retrieval on the day, so neither appears — their absence is a limit of this sample, not a judgement.

Finally, this is a cost comparison and not a currency one. Converting pounds into dollars takes on dollar exposure, and the size of that exposure dwarfs any charge discussed here. A 1.59% move in the spot rate over eleven July trading days was worth more than a year of the dearest FX charge on the £1,000-a-month pattern.

What would change the conclusion

A published base rate. If platforms disclosed the wholesale rate they received alongside the margin they added, the comparison above would become checkable rather than indicative. The FCA rules already treat an embedded mark-up as a disclosable cost; the tariff pages express it as a percentage of an unnamed number.

Aggregation across a day. If a platform applied its tiers to total daily or monthly conversion value rather than per deal, the £160.40 penalty on a £3,000 monthly pattern would disappear at a stroke. Nothing in the published cards suggests any of them do this today.

Commission pricing spreading. Interactive Brokers charges a minimum of USD 2.00 an order and passes the rate through. If that structure reached the mainstream UK platforms, the percentage cards would look expensive very quickly on small, frequent conversions — and much less so on a single large one.

The thing worth watching isn't the headline percentage. It's how many times a year you cross the currency line, and whether the way you hold the asset requires you to cross it at all. LedgerTouch counts the crossings; a spreadsheet and a contract note will do it too.