The sum payable
The sum payable must be a sum which is certain, allowing for the variables set out in s14:
14 Sum payable
(1) The sum payable by a bill is a sum certain within the meaning of this Act, although it is required to be paid with, by or according to, as the case requires, any one or more of the following, namely:
(a) interest or bank charges; or
(b) stated instalments; or
(c) stated instalments, with a provision that upon default in payment of any instalment the whole shall become due; or
(d) an indicated rate of exchange, or a rate of exchange to be ascertained as directed by the bill.
(2) Where more than one sum is expressed to be payable in a bill, the lesser or least, as the case may be, of the sums so expressed to be payable shall be taken to be the only sum ordered to be paid by the bill.
(3) Where a bill is expressed to be payable with interest, unless the instrument otherwise provides, interest runs from the date of the bill, and if the bill is undated from the issue thereof.
The ‘sum certain’ must appear on the face of the bill of exchange: Lamberton v Aiken (1899) 37 SLR 138 (which referred to interest); Rosenhain v Commonwealth Bank of Australia (1922) 31 CLR 46 (interest); Standard Bank of Canada v Wildey (1919) SR (NSW) 384 (considered the term ‘all the bank charges’ was uncertain); Tropic Plastic Packaging Industry v Standard Bank of South Africa Ltd (1969) 4 SALR 108 (currency rate of exchange with additional words making the amount uncertain).
Where the amount payable is stated in words and numbers, an inconsistency in some jurisdictions is not uncertain as the rule make the amount stated in words payable, see s14(2) and also in the UK s9(2), US UCC s3-118(c), Canada s28(2), NZ s9(2), South Africa s7(2), India s18 and countries which have adopted the Geneva Convention Art 6.
Taken from 3.1 Bills Of Exchange 7-7-6.doc