Practical definitions, worked figures, limits, and source checks for cash planning, investing, taxes and currency.
HMRC publishes a monthly exchange rate on the penultimate Thursday of each month, based on the midday rate the day before publication, and that rate applies to customs declarations and …
A bid-ask spread is the gap between the price a buyer will pay (the bid) and the price a seller will accept (the ask) for a currency pair; multiplying that gap, measured in pips, by a p…
The IRS states it has no official exchange rate and generally accepts any exchange rate that is used consistently, while publishing its own yearly average currency exchange rates for tr…
The Kuwaiti dinar's minor unit is the fils, one thousandth of a dinar, not the hundredth most currencies use, so a conversion into KWD carries three decimal places rather than two. At a…
The Japanese yen has no minor unit in current circulation, so a currency conversion into yen is rounded to a whole number, not two decimal places. At an illustrative rate of 150.35 yen …
The Qatari riyal has been pegged to the US dollar since 1980, with the peg formalized by Royal Decree No. 34 of 2001, and Qatar Central Bank states it buys dollars at no more than QR 3.…
The CFP franc used in French Polynesia, New Caledonia, and Wallis and Futuna has been fixed to the euro since January 1, 1999, at a legal parity of 1,000 XPF to 8.38 euros, which is 1 e…
Visa states that the exchange rate it uses for a currency conversion is the rate in effect on the day Visa processes the transaction, not the date of the purchase or the date it later p…
Accounting software books a foreign-currency invoice at the exchange rate on the invoice date, then compares that booked value with the exchange rate on the date it is actually paid; an…
For a one-time expense on a specific date, the IRS's general rule is to use the spot rate prevailing when the amount is paid, not a yearly-average table meant for income received evenly…
A do-it-yourself conversion with a built-in markup multiplies the amount by the market rate and then by one minus the markup percentage: converted amount = amount times rate times (1 mi…
The total cost of a currency conversion is the mid-market equivalent amount minus what the recipient actually receives, combining any rate markup with any flat or percentage fee into on…
The Additional Medicare Tax adds 0.9% on top of the regular 1.45% Medicare tax for wages above $200,000 for most filers, $250,000 for married filing jointly, and $125,000 for married fi…
For the 2026 tax year, the IRS standard deduction is $16,100 for single filers and $32,200 for married couples filing jointly; a single filer with $14,700 of itemizable deductions is be…
Paying a $115.38 biweekly health insurance premium through a pre-tax Section 125 cafeteria plan, instead of after taxes, leaves an employee with $34.21 more net pay per paycheck under a…