USD top up from HSBC USD bank account charges applied

I transferred 2 amounts from a HSBC USD bank a/c to a Revolut USD account over the last 2 months.

The first transfer went through with no intermediate beneficiary charges the second transfer had $25 deducted.
Nothing had changed except the 2nd one was 1000 usd more.
How can this be?
By the way the Revolut statement showed no charges? Surely if Lloyds (Revolut beneficiary) took thecharge then it should be on the statement.

Hey there!

Revolut does not charge a fee to top up your account via bank transfer. However, it is important to watch out for third-party fees.

If your transfer is in EUR or CHF and your bank is using SEPA (Single Euro Payments Area) then a transfer to Revolut will cost the same as a domestic transfer. SEPA includes the 28 E.U. member states as well as Switzerland, Norway, Iceland, Liechtenstein, Monaco, and San Marino. If your transfer is in PLN, USD or any other currency then it will likely be sent via SWIFT. This means that your bank (and/or an intermediary bank) could charge you an international transfer fee.

With SWIFT transfers there are a few things to bear in mind:

When your money is in transit, it may be processed by an intermediary bank. They may also deduct a handling fee.
Depending on which fee option (SHA, BEN, OUR, REM) you choose while doing a SWIFT transfer to Revolut, intermediary, originating bank and beneficiary bank (namely Lloyds) can apply a handling fee for that transfer.
As banks charge different amounts and are not always transparent, we cannot provide an accurate amount you would be charged.
If your top up is in a currency other than our supported holding currencies, your bank will convert the money using their exchange rate. This is unlikely to be the interbank rate, and you might also incur a currency-conversion fee