Barnes & Noble announced this afternoon that customers interested in buying a new NOOK Color or NOOK Simple Touch will be able to save $20 on its original retail price if they purchase them using a Mastercard card.

Starting today and running until March 18, Barnes & Noble customers can redeem the offer at its 700 US retail stores or via the website, providing another reason to look at the retailer’s e-reader range over rival Amazon Kindle devices.

The NOOK Color traditionally retails for $169, but from today it will be available for $149. The NOOK Simple Touch sees the $20 reduction take it down to $79, but only for the next three days.

To take advantage of the offer, you need to add one of the B&N devices to your basket, prepare to enter your Mastercard card details, but also to add in a coupon code. The offer is not available for the NOOK Tablet.

In the UK, consumers have taken to Amazon’s Kindle range. Despite some competition from the likes of Sony, Kobo and, well, Apple’s iPad, there hasn’t been a real contender for Amazon’s crown. However, that could be changing with US bookseller Barnes & Noble hosting a developer workshop in London just a day after the NOOK promotion ends in the US.

This could signal a move into the UK market from Barnes & Noble later this year, but for now the company is doing what it can to trouble Amazon domestically.