Are you one of 9 million overpaying for your mobile? Time to STOP 

Via the cheapest ever Sims (eg, £4/month for 15GB data) & contracts for iPhones 13, 14 & Samsung S22s

Whether you just want to cut your bill, or feel it's time to upgrade your handset, this is a sweet-spot moment to sort it. Deals after Black Friday are still white-hot and there's a raft of 'cheapest-evers' out there. We asked Martin what to call it, he said 'Carpe Dealum' (so we included it, mainly because he's our boss!).

Know what you want? Our Cheap Mobile Finder tool includes the top Sims, handsets and lots more.

Sims are the little chip that goes into your phone and dictates the network and tariff. Millions who are out of contract can simply change to a cheap Sim and pay far less than right now. And there's no need to change your number.

As MoneySaver Jane emailed: "Thanks to Martin's article on mobile Sim-only deals, I saved £48/month [£576 a year]. Incredible saving - thank you." Here's a selection of current cheap deals, all including UNLIMITED calls and texts:

• 6GB/month for '£3.38/month'. Ends Thursday. This no-frills MSE Blagged Lycamobile Sim (uses O2's network) costs 85p for 6 months, then £5.90/month on a one-month rolling contract - we've averaged the price over a year. Lycamobile doesn't offer Wi-Fi calling or 5G on iPhones.
  This should be enough data for those who use their phone for emails, light web-browsing, social media, watching a few short videos each day and streaming the odd podcast.
  
  
• 15GB/month for '£4.25/month'. This iD Mobile Sim (uses Three's network) is £8/month, but you can claim a £45 Amazon, Tesco or Uber Eats voucher. Factor that in and it's equivalent to £4.25/month over the 12-month contract.
  Better for those who spend quite a bit of time web-browsing, streaming videos and downloading podcasts.
  
  
• A HUGE 100GB/month for '£9.87/month'. This TalkMobile Sim (uses Vodafone's network) costs £11.95/month, but you can CLAIM (don't forget) a £25 Amazon voucher. Factor that in and it's equivalent to £9.87/month over the year's contract.
  This should be enough data for most people, even if you use your phone to stream a lot of videos each day or use it for tethering.

Sticking with your current handset and switching Sim is cheaper and greener. But if you need a new phone/or really want one (and can afford it), now's a good time, with some of the cheapest prices we've ever seen. Though if you're doing it for more storage, first check our 14 ways to boost mobile storage. Here are our top tips...

• Is the latest handset really worth it? There's a big premium on the latest handsets, but cynics (like us) would note in the good old days firms would launch the Swish-5 handset, then when it improved they'd call it the Swish-5.1. These days even minor iterations jump a full number (so to Swish-6). So try these tools.
  
  - Find me a phone lets you say what you want, then finds the cheapest handsets that fit the bill. 
  
  - Find me the best phone within my budget does just that.
  
  
• The 'buy a phone & Sim separately' rule is not clear-cut. That used to be cheapest, yet over the last year or so we've seen some contract deals with a lot of data massively undercutting that. Our cheapest new handset tool includes both options across most phone models.

• Even better, why not cut the cost with a refurb phone (with warranty)? Top-grade refurbished models are often just returned by customers who have changed their mind, while firms have other 'grades' or ratings that allow you to unlock even bigger savings. These may have small signs of use but still perform like new.
  
  Refurbs usually come with a warranty (often 12 months) but you generally just get the phone on its own, with no charger or other accessories. Savings can be huge though, for example:
  
  - New iPhone 12: £629
  - 'Pristine' quality refurb: £399
  - 'Very good' refurb (signs of light use): £379
  - 'Good' refurb (a few scratches): £358
  
  To find whether your phone has decent options just opt for refurbs in our comparison filters. We don't list any rated lower than 'good'. 

Whether you're choosing a new Sim, or a whole new phone, these tips may help you cut costs further:

• Happy where you are? Haggle to cut costs. Mobile firms are among the easiest to haggle with - success rates for those who try are over about 70%. So use the tools above to benchmark your top deal, then see our haggling tips for how to get your provider to beat it.
  
  As David emailed: "I contacted my provider EE as I was paying £13/month-ish for 1GB data plus unlimited calls and texts. I followed your guidelines and now pay £8 for 6GB with unlimited calls and texts. Cheers."
  
  
• Add a spending cap to stop eye-watering bills. If you use up your monthly data allowance, buying extra isn't usually cheap. But if you add a spending cap to your account, you'll never spend more than you can afford. See how to set your personalised spending cap.
  
  
• Members of cashback sites may be able to get deals even cheaper. These sites often give cashback on Sim-only and handset deals, and in some cases, they can undercut promotional deals elsewhere. But don't assume they're the same deal: they can be structured differently, so check carefully. See Top cashback sites for more.
  
  
• Flog old mobiles - for example, £246 for an iPhone 11. If your phone is still usable there are sound financial and environmental reasons to recycle your old handset, as they can give off potentially noxious substances as they decay.
  
  You could pop the handset on eBay, or for ease, use one of the dozen or so phone-buying companies out there. To find the best payer, there are comparison sites including Sell My Mobile*, Compare and Recycle and Compare My Mobile* - use at least a couple for the widest possible search.
  
  Firms usually promise payment via bank transfer within one day of receiving your phone. If something goes wrong, unfortunately you've little protection, so check reviews first. More info in Sell old mobiles.