has today launched what's likely to be the largest collective switch to date and we've negotiated tariffs cheaper than the cheapest energy deals using the power of the 9m recipients of our weekly email and the 1.2m members of Cheap Energy Club.

This is a huge opportunity to beat the market's cheapest gas and/or electricity deals before turning up the heat for winter. In the past I've struggled to support collective switches – where a 'trusted intermediary' (such as a council or us) runs an auction for energy firms to bid to provide special deals for its members.

My problem was most were more expensive than the market's cheapest. Yet now it's coming of age, so we've used our enormous user base – 9m email recipients and 1.2m Cheap Energy Club members – to make it come up trumps. Watch my three-min video explaining how the collective switch works.

1. How to grab one of these tariffs 

It's ONLY ON FOR TEN DAYS, ending 5pm Friday 7 November, and collective switch rules mean it needs to be via our free Cheap Energy Club. Fill in your details (it's better if you've bills, but if not it can estimate) then it'll...

  • Show your exact price for the tariffs and compare them to ALL tariffs on the market (unlike other comparisons we do this by default).

  • Give £30 cashback – on dual fuel if you switch (£15 electricity only).

  • Monitor that it stays cheap. You set a 'trigger saving', eg, of £50, then we monitor your rate and alert you when you can save that amount switching again. This is great for fixed deals where cheap rates only last a year or two and takes the hassle out of being an energy tart. 

  • Know someone overpaying? Spread the word to help cut energy bills.

2. MSE Big Winter Switch Event Winner 1: The CHEAPEST tariff 

Our winner's this E.on MSE collective 12 month fix for both dual fuel and electricity only. It's the cheapest tariff, the rate won't rise for a year and it has far lower early exit fees than the next best deals.

Plus you get £30 cashback via the Energy Club (£15/fuel) and it offers 1,500 E.on points, which can be converted to a £15 high street voucher or 1,500 Tesco Clubcard points (worth up to £60 on rewards, see our Reclaim and Boost Tesco points guide).

How it compares 
(average price for typical dual fuel direct debit user) 

Winner: E.on 12 month fix (ie, November 2015). £950/year – £5/fuel exit penalty
Next cheapest: Extra fix till 31 October 2015. £976/year – £25/fuel exit fee
Typical cost: On a big six energy firm standard tariff: £1,180/year 

Get YOUR EXACT PRICE for it (and full market comparison)

  • Good for you if: You just want the lowest price and don't mind moving tariffs regularly as it's only definitely cheap for a year. 

  • Not for you if: You're moving home soon (it's not portable), or if you just want to get a cheap deal you can forget about for a longer term. 

Customer service feedback for E.on: It's mid-way, with 43% of voters saying it's "great" and 17% "poor" in our August customer services poll.

3. MSE Big Winter Switch Event Winner 2: The cheapest LONG fix 

Our winner's this Scottish Power MSE collective 3-year fix. This long dual fuel or electricity-only fix ensures no price hikes until December 2017 and is typically £40 cheaper than the next cheapest over that period. Plus you get £30 cashback via the Energy Club (£15/fuel). 

How it compares 
(average price for typical dual fuel direct debit user) 

Winner: Scottish Power fix till 31 December 2017. £1,099/year – £30/fuel exit fee
Next cheapest: First Utility fix till 31 January 2018. £1,136/year – £30/fuel exit
Typical cost: On a big six energy firm standard tariff: £1,180/year

Get YOUR EXACT PRICE for it (and full market comparison)

  • Good for you if: You want a cheap price which you can forget about for the next few years. Useful if you don't usually switch. 

  • Not for you if: You're moving home soon (it's not portable). 

Customer service feedback for Scottish Power: Only 18% of voters say it's "great" with 55% saying "poor" in our August poll. However, also see point 7 below as it has agreed to provide special customer service arrangements for our collective switch.

4. MSE Big Winter Switch Event Winner 3: The cheapest GREEN tariff

Our winner's this Green Star MSE collective 12 month fix tariff, by far the cheapest tariff fitting Ofgem's (soon to be introduced) Green criteria - including carbon offsetting, renewable generation and more. 

The tariff is available for dual fuel or electricity only and prices won't rise for at least a year. Plus you get £30 cashback via the Energy Club. 

How it compares 
(average price for typical dual fuel direct debit user) 

Winner: Green Star 1 year fix. £1,055/year  – £30/fuel exit penalty
Next cheapest firm: Good Energy variable. £1,285/year – no fee
Typical cost: On a big six energy firm standard tariff: £1,180/year 

Get YOUR EXACT PRICE for it (and full market comparison)

  • Good for you if: You believe in green causes, but don't want to pay that much more – and may be prepared to switch again in a year. 

  • Not for you if: You want a firm with a good customer service record or you plan to move home soon and want to take the tariff with you.

It's a fairly new provider so we don't have substantial feedback for it. Yet we've arranged bespoke customer service.

5. Next week: Top PREPAY fix tariff 

Prepay users are often excluded from collective switch deals but we were determined not to let that happen. So coming next week we will be launching our winner especially for those that have a key/card meter.

6. Do you make money from this? 

Yes. Energy suppliers pay introducer fees of about £60 per dual fuel switch for comparisons and collective schemes. Of that we give £30 back to you as cashback, to encourage you to switch. 

The remainder is used to pay our suppliers: (part of the same parent group as MSE), which provides the underlying data and switch process; and Allfiled, which provides the technology database platform. 

Depending on how successful this is, we expect to be left with about £11 per dual fuel switch – just over a third of what we give in cashback. That will pay the team who work on this, and we hope it will also leave some profit too. 

As always, we only ever write based on editorial independence in the consumer interest as guaranteed by the legally binding editorial code.

7. Who's responsible for these tariffs, MSE or the energy firm? 

It's the energy firm which is responsible for supplying you, and you pay it. We're not officially responsible, but we take our duty for organising this seriously. 

So as well as working with them in advance to iron out any problems, we've asked all the providers to set up special teams with separate phone numbers or 48 hour response times to help on our switch. The Big Winter Switch Event help page has full details, plus how to get in touch with us if all else fails.

8. Will these definitely be the cheapest deals? 

They are the cheapest at the time of writing (based on typical use, averaged across the regions). Yet we can't say they will be for the whole ten days – in fact we hope while the Big Winter Switch Event is on other providers will respond and cut their prices too, in which case when you do the comparison in the Free Cheap Energy Club you'll see them.

9. When you switch ensure your old provider gives you back your credit 

As most people's last bill was a summer one, if you pay by monthly direct debit you're likely to be in credit now – it could be by £100s. When you switch you should be given that cash from the firm you're leaving, but some won't cough up unless you ask.

However, don't spend it - the safest thing is to put it towards winter's bills. And remember the new provider may estimate your usage differently – if this is too high you've a right to ask it to be lowered. 

PS: If you've switched before in the last five years you may not've been given credit owed. If so you can still get it, see Reclaim energy credit.

10. Final quick tips to slash energy costs 

Of course, it's not all about the tariff – there are a lot more ways to slash your bills. 

  • Get FREE loft/cavity wall insulation, open-to-all. Can save £290/year.

  • Pay by monthly direct debit. It's typically £70-£90/year cheaper.

  • If you pay by monthly direct debit, always do regular meter readings.

  • Don't haggle – it's a waste of time. Energy firms can't offer specials.

  • Get grants and free help if you're struggling to pay. See Energy Grants.

  • In energy debt? You can still switch (if less than £500 on prepay).

  • Renter? You've a right to switch too. Free factsheet for your landlord.

  • Use heating oil? People power helps here. See Cheap Heating Oil.

  • Can't get a complaint resolved? Use the free Energy Ombudsman.

  • Don't walk round in your boxers, turn the heat down and dress up.

Want to ask me (Martin) an energy question? 

I'll be doing a live Twitter Clinic from 16:45 for 15 minutes today (29 October) – answering all questions sent to @MartinSLewis about the collective switch. Use the hashtag: #MSEenergy.