OK so its not exactly Whistles, but here are two more magazine based money off vouchers.
Grab the April edition of Cosmopolitan magazine (£3.30 with Fearne Cotton on the front); in the booklet that comes with the larger edition of the mag you'll find a voucher for 20% off at New Look. You should also find another voucher inside the mag itself. Both are valid in store from Monday 9 - Sunday 29 March. Use them on a single transaction on either full price or promotional items (but not permanently reduced products).
Get the mag and you'll also find a 20% off code to use online at New Look, valid on Saturday 28 and Sunday 29 March. Note that if you're only planning to buy Cosmo for the offer, you'll need to spend over £16.50 in store for the 20% discount to be worth the cost of the mag.
20% off Uniqlo - Magazine based voucher
To get 20% off at Uniqlo simply take page 145 of April's Glamour magazine (£2 with Nicole Richie on the front) to your nearest Uniqlo store before Saturday 4 April 09. Grab the mag and you'll also find a 20% code to use online.
The voucher is valid for one transaction only and cannot be used with any other discount or offer.
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