Nectar points double-up and free Santa letter

Sainsbury’s Nectar double-up, 20% off gift cards, free Santa letter, Megabus seats and a chocolate lolly. These are our Money Saving Expert Martin Lewis’ Deals of the Week.

Remember, deals can change quickly, even while I’m on the programme. So always double-check the terms and conditions before spending. Plus, while I hope these deals will save you cash, don’t spend if you can’t afford it, don’t need it, or won’t use it.

Sainsbury’s Nectar points double-up

Until Tuesday, Sainsbury’s has launched a short-term double-up of the value of your Nectar points when you exchange them in store. So, you’ll be able to swap 1,000 points for a £10 voucher instead of the usual £5 – though the most you can exchange is up to 4,000 points per department, so max £40.

Exchanged vouchers can only be used in seven of Sainsbury’s departments:toys, electrical, entertainment, homeware, seasonal goods (so Christmas goodies) Taste the Difference wine – champagne, sparkling, sherry or port – and Tu clothing. This can be used in conjunction with other offers, eg, Lego Duplo on sale as buy any two for £20, so you could pay for that with 2,000 points.

You must swap and use the vouchers by next Tuesday – if you don’t you won’t be able to swap them back into points.

Free letter from Santa for kids

If your child writes a letter, which includes their name and address, toSanta/Father Christmas, Santa's Grotto, Reindeerland, XM4 5HQ bySunday 6 December, he or she should receive a personally addressed reply from Santa and his elves before Christmas Eve. But in the past there were some reindeer issues that meant non-delivery, but Royal Mail says it’s got more elves helping this year, so while it’s a nice freebie, it’s not a definite.

For a recommended £5 donation, the NSPCC also offers a similar service, which has more certainty and the money donated goes to ChildLine.

If your child is blind or partially sighted, they can get a free reply in Braille, audio or large print from Santa’s special elves at the RNIB. Write to: Santa Claus, RNIB, PO Box 173, Peterborough, PE2 6WS by Tuesday 1 December and include name, address, contact number, preferred language and preferred reply format (either uncontracted/contracted Braille, large print including font size or audio CD). Or email santa@rnib.org.uk by Friday 18 December and they'll get an email reply from him.

Martin’s Quickies:

- 20% off gift cards which can be used in January sales: Discounted gift cards are rare but till this Sunday 22 November at Tesco you can get 20% off gift cards for iTunes, New Look, Accessorize, Monsoon and Pizza Express and Mitchells & Butlers restaurants. So buy £100’s worth and it’ll only cost you £80. Plus you can get an extra 150 Clubcard points if you buy over £50 worth. Better still as these all last at least a year, it means you can buy now to use in the January sales.

- Free Thorntons chocolate lolly: Go to VoucherCodes and enter your email address (this will sign you up to its site but you can cancel after) and you’ll be sent a voucher with a code which you can print or show in mostThorntons stores to get a free £1ish chocolate lolly. The code is valid until this Sunday or until all 40,000 that are left go (there were 50,000 to start with last Thursday).

- Free Megabus seats: Budget coach travel provider Megabus is giving away 50,000 free one-way seats on all its routes in England, Scotland, Wales and Europe, including Amsterdam, Milan and Barcelona, for travel between Tuesday 12 January and Friday 12 February. The free seats are released 60 days before travel (so for travel between 12-18 January seats are already available) and are available for every day including weekends, though they may be tricky to find as different routes will have different numbers of free seats available. If you do spot one the price will show as £0.00 and you have to pay a 50p booking fee per transaction, not per ticket.

Web exclusive: Up to 60% off M&S

Go online to M&S or into a store and you'll be able to get up to 60% off selected womenswear, menswear and kidswear. Go quick if you want something, as stock is limited. Delivery's £3.50 or you can collect in store for free.