Amount in Words

Type a figure and get it written out properly: British or American form, the pence or cents in words or over one hundred, the plurals correct, and the hyphens where they belong. Copy it onto a cheque, a contract or an invoice.

It looks like a formatting job and it is a legal one. Under section 9(2) of the Bills of Exchange Act 1882, where a sum on a bill is expressed in both words and figures and the two disagree, “the sum denoted by the words is the amount payable”. A cheque is a bill of exchange, and most jurisdictions that inherited that statute kept the rule. The words are not a caption for the number. Where they differ, they are the number.

Which is why the small things are worth getting right. Twenty-one takes a hyphen, because “twenty one” is two words and reads as two figures. British English writes one hundred and one where American English writes one hundred one.

The amount is read digit by digit rather than through a floating-point number, so 0.29 becomes twenty-nine cents rather than twenty-eight. Nothing you type is uploaded. There is no reason to send a payment amount to a server to spell it out.

Writing a sum twice, in two different notations, is one of the oldest error-detection schemes there is, and it predates cheques by centuries. Figures are compact and fragile: a stray stroke turns 100 into 1,000, and a decimal point is a single dot. Words are long, redundant and very hard to alter convincingly. Requiring both, and giving one of them priority, means a single mistake or a single alteration produces a visible disagreement rather than a silent loss.

English law settled which one wins in 1882 and it has not moved since. Section 9(2) of the Bills of Exchange Act provides that where the sum payable is expressed in words and also in figures and there is a discrepancy, the sum denoted by the words is the amount payable. That statute was exported widely, so the same rule holds across much of the Commonwealth, and comparable provisions exist elsewhere: the practical consequence being that in most places, if you write one figure and say another, you have paid what you wrote in longhand.

This is also why cheques attract conventions that look fussy until you know what they are for. “Only” at the end closes the line: five hundred pounds only cannot become five hundred and fifty pounds by the addition of two words. A line drawn through the remaining space does the same job. None of these are decoration; each one closes a specific gap that has been exploited.

The hyphen matters for the same reason. Every compound number from twenty-one to ninety-nine takes one, and without it the string is genuinely ambiguous: “twenty one pounds” could be read as twenty-one or as two amounts run together. The written form exists precisely to remove ambiguity, so a written form that introduces some has failed at its only job.

The “and” is different. It is a real dialect split rather than a correctness question. British English inserts it before the tens and units within a hundred group, giving one hundred and one, and that is standard in the UK, Ireland, India, Australia and New Zealand. American English omits it. Neither is wrong. What is worth knowing is the subtler placement rule underneath: “and” belongs before the final group only when that group is under a hundred, so it is one thousand and one but one thousand one hundred and one. A tool that puts “and” after every scale word gets this wrong on exactly the amounts people write most.

One thing to be careful of on international documents is the word billion. In English-language finance it means a thousand million and has done for decades, which is what this uses. Older British usage (and several European languages still) make it a million million, a thousand times larger. On a domestic cheque this never arises. On a cross-border contract drafted in translation it occasionally has.