A to Z of financial terms

See our definitions to help you understand financial and legal terms.

First published: 20/03/2023 Last updated: 20/03/2023

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Bill of sale

Allows individuals to transfer ownership of their goods to a lender, normally as security for a loan until it's repaid. They're mostly used for logbook loans. Bills of sale have fewer consumer protections compared with other forms of lending (for example, because lenders have strong rights to seize the goods).

Binary option

A type of fixed odds betting, which has been banned in the UK since April 2019. Read more about binary options scams and how to protect yourself


Bitcoin is a type of cryptocurrency or electronic payment system that operates independently of a central bank. Read more about cryptoassets.

Boiler room scams (share bond)

Scammers pretend to be stockbrokers who then pressure you into buying worthless, over-priced or non-existent shares or bonds. These types of share and bond scams are often run from ‘boiler rooms’ overseas. Read more about share or bond scams and how to protect yourself.

Breakdown cover

Provides assistance if your car breaks down and it needs repairing or taking to a garage. We don't regulate breakdown cover, so you may not be able to complain to the Financial Ombudsman Service if something goes wrong. Read more about complaining about vehicle breakdown cover on the Financial Ombudsman website.


Brokers will arrange transactions between a buyer or a seller, such as buying insurance or getting a mortgage, in exchange for a commission.

Buy now pay later (BNPL)

Refers to different types of credit or borrowing. There are generally 2 types of BNPL: the regulated type that’s usually interest free for the first 12-months and used to buy larger items like sofas, carpets or furniture. Because these are regulated products you should be protected if something goes wrong. But some BNPL is unregulated. This is still interest free, but it's usually repaid in around 3-months and used to make smaller purchases, such as clothes. Find out more about BNPL from MoneyHelper.