The charity has hired telemarketing firm The Listening Company to contact supporters who have so far failed to opt in to the programme, which allows charities to recover over 28p in every 拢1 of tax contributions made by its supporters.
The appointment follows last year's successful campaign, which generated an additional 拢1m in the first year.
Pierino Cioffi, appeals director at Oxfam, said: "The Gift Aid scheme is a great way for our tax-paying supporters to ensure that the money they donate stretches as far as possible for the causes we support. Telemarketing has proved to be the ideal way to talk to those supporters who have not responded to us in other ways."
Supporters are initially being contacted by Oxfam by mail. The Listening Company will then make as many as 20,000 calls to supporters, urging them to verbally agree to the scheme or promise to return consent forms.
The drive also enables Oxfam to find out which supporters are non-taxpayers and not eligible to join the scheme. Their names can then be scrubbed off the database and Oxfam can save money on the initial mailing.
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