'January' 50%+ sales ON NOW

Huge 50%+ sales under way. The Boxing Day and Jan sales now begin before Santa's even down the chimney. A few stores even let you order online on Wed to arrive by Xmas if you pay full deliv (eg, Asos, order by 8pm Wed, £6 p&p - see Xmas last orders & deliv costs).

Below, we've a rundown of the top 20 sales (see the full 60+ Boxing Day and January sales), and your rights. Plus we reveal which giants boosted sales last winter from their original discount, to help predict if it'll happen again – yet there's no certainty and stuff may sell out.

Big 20 'Boxing Day' & 'January' sales

Your sales rights

1. You've NO legal right to change your mind if you buy in-store. You're only entitled to a refund if faulty. Otherwise you can only exchange if the store's published returns policy says so, and what it says goes - so if you need a receipt, you need a receipt. Plus many stores suspend these policies during sales, so never buy anything and assume it’ll let you change it. See Buying Rights.

2. Buy online and you DO have the right to change your mind. The Consumer Contracts Regulations mean if you order online or by phone, you have 14 days to cancel your order and a further 14 days to return goods, regardless of reason. These items are excluded so can't be returned or cancelled (see full online buying rights):

• Personalised goods (eg, photo mugs), unless faulty.

• Fresh food and flowers, unless faulty.

• Travel, hotel and event tickets.

• Opened games, videos or software, unless faulty.

If you click and collect at stores, you're covered. If you just reserve (but don't pay online), you're not. What matters is where you pay.

3. If faulty, return quickly and you DO have refund rights. The game changes if goods are defective. Stores' policies are irrelevant as your statutory rights allow a refund if you're quick. Shops may fob you off - eg, "go to the manufacturer" or "no returns even if faulty during sales". They're wrong. See What Shops Get Wrong and Return Rights.

Buying 2nd-hand from stores/traders (not individuals), gives you the same rights, though what's "satisfactory quality" varies from a 10p T-shirt to a £2k bag. See 2nd-Hand Rights. Related: 40 eBay Tricks.

4. Pay by credit card for extra protection. Buy anything at £100+ and pay even 1p by credit card (not debit) and Section 75 laws make the card firm jointly liable. If goods are faulty, or the retailer goes bust, it must pay up as if it were the shop.

REPAY IN FULL each month, preferably by direct debit, so there's no interest. In which case... get 5% cashback too: the Amex Platinum Everyday* card has no annual fee and pays 5% in the first three mths (max £100), then up to 1.25% (fail to repay in full & it's 22.9% rep APR). Full info and other options in Cashback Credit Cards.

5. Martin's Money Mantras. Always check Martin's Money Mantras. If the answer's 'no' to any of them – DON'T BUY.

This article first appeared in the weekly email on 23 December 2015.