Why your international payment isn't there yet

There's a law that says a euro payment has to arrive within one business day.

Domestic UK transfers in pounds get the same guarantee.

But send US dollars to a supplier in Ohio? It might take 24 hours, or it might take four days. If you ask your bank how long does a SWIFT transfer take on that route, you won't get a clear answer because there isn't one.

Dollars don't get the same legal protection. Neither does yen, or dirhams, or almost anything else. So once pounds and euros are out of the picture, how long do SWIFT payments take comes down to whatever speed the provider feels like basically, and whatever the industry manages that particular day.

A lot of what eats the time is surprisingly ordinary:

• Missing cut-off times: Handing your bank a transfer two minutes late, which pushes the whole thing to tomorrow
• Time zone gaps: Your evening is somebody else's 3am, and nothing moves till they're back at their desk
• Data mismatches: A typo, a slight mismatch in the recipient's name, a missing reference
• Surprise bank holidays: A public holiday in another country, which nobody warns you about

That last one is more common than you'd think. Pay a US supplier the week of Thanksgiving and the payment can just sit there for two extra days, because their banks are suddenly closed on a Thursday.

Even once the money's technically arrived, it's not always visible straight away.

Some banks batch-process incoming payments rather than crediting them the second they land, so there's often one last quiet stretch right at the end too.

Not every payment crawls - banks running SWIFT's newer gpi system settle roughly half their payments within half an hour. Same network, same job, just better tracking and fewer places for a payment to quietly go missing. Trouble is, that you can't tell from your side whether both banks in the chain are running that newer version, which is quite a big part of why the same kind of payment can take an hour one week and four days the next.

If you're already three days in and starting to worry, two things help:

First - count business days, not calendar ones.

A transfer sent Thursday afternoon can look three days late by Monday morning when only one actual banking day has passed.

Second - if it does seem stuck, call your own bank first. They're the ones who can see the whole trail.

Might as well build in a two-day buffer on anything that isn't pounds or euros, since the honest range is one to five days. Your supplier waiting on an overdue invoice won't care why it's late, just that it is.

There's a way round this entirely for both pounds and euros: don't convert at all.

Pay a UK supplier from a GBP balance, or a European one from a EUR balance, and the payment rides Faster Payments or SEPA with that legal guarantee still attached, since it never needed converting to begin with.

The dollar side doesn't get the same fix.

Holding USD instead of converting into it saves the conversion cost and the extra step, but it doesn't buy back the legal guarantee, that's tied to the currency itself, not to whether the money was already sitting there. A USD payment to a USD supplier stays a USD payment either way.

Ampere holds GBP, EUR, USD and CHF as separate balances, which covers the pound and euro side of this. The Mastercard rate shows up before you pay, so at least that part isn't a guess. Try the currency calculator yourself and see today's number.

How long swift transfer takes always came down to which currency you picked, pounds and euros on one clock, everything else on none - a dollar payment still won't arrive instantly, but it’s good to know which clock is running.