What countries use "bond" to refer to a security deposit?

Solution 1:

Bond is a UK term for security deposit.

Apart from the U.S., most of the former colonies use UK terminology, so at minimum, the term bond is used this way in Australia and New Zealand.

(I don't know about Canada).

Also, keep in mind that in the UK deposit in a financial context denotes what we call down payment (for a house, car, etc.) in the U.S.

Solution 2:

Although some variations in English usage between countries can be attributed to custom or even fashion, the status of this use of bond in Australian English is quite well established.

The Residential Tenancies and Rooming Accommodation Act 2008 of the Queensland Parliament includes the following definitional clause.

111 Meaning of rental bond
(1) A rental bond, for an agreement, is an amount—
(a) paid by or for the tenant under the agreement; and
(b) intended to be available for the financial protection of the lessor against the tenant breaching the agreement.

When (usually young) tenants are changing accommodation, whether or not they have done too much damage to "get their bond back" is a major concern.