Although there is no extra interest on payment or return on premiums paid. (moneygyaan.com)
Cavanagh v. Minister of National Revenue 2013 FCA 94 Income Tax — Deductions in computing income — Alimony Cavanagh was ordered to pay support in a specified amount per week as well as interest on any payments in default, from the date of default. (slaw.ca)
No, there is no credit card surcharge, however your credit or debit card issuer may charge you a foreign transaction fee and / or interest on payments deducted in GBP. (britishairways.com)