E.ON has become the first of the so-called 'Big Six' energy suppliers to announce a price cut this winter.

It will reduce its standard gas prices by 5.1% from February 1.

E.ON claims the cut amounts to a saving of £32 off an annual gas bill for the average household. However, those on standard tariffs can typically save much more by switching onto a new deal.

At the same time the firm has also launched a new one-year dual fuel fixed product, which it claims is the cheapest deal around. The Energy Fixed One-Year v18 will cost a typical household £783 a year and is open to new and existing customers.

Wholesale prices plummeting

Over the last week both energy regulator Ofgem and politicians have expressed concerns that gas prices are not being cut in line with falls in wholesale prices and have called on firms to act.

While E.ON is the first to bow to this pressure, its 5.1% cut seems tiny compared to the amount by which wholesale prices have actually dropped. The price of wholesale gas has tumbled 34% over 2015 according to market information provider ICIS.

But Toby Crocker, chief executive of E.ON, defended the size of the price cut: "The underlying position is that whilst the price we pay for our customers’ energy has fallen, we also have to take account of managing the various other risks in the market which can change, and the fact that many of the other costs that we don’t control but do have to bear have increased or may increase.”

If the pattern of previous years is repeated E.ON's price cut will now lead to the other 'Big Six' suppliers cutting their prices, although British Gas cut its gas prices by 5% back in August so it will be interesting to see if it does so again.

The cheapest energy deals

Here’s a round-up of the cheapest tariffs right now if you opt for both fuels from one supplier (known as dual fuel), pay by monthly direct debit and manage your account online. The price includes both the unit rate and any standing charge.

Energy supplier

Tariff

Type of tariff

Average annual cost

E.ON

Energy Fixed One Year v18

Fixed for 12 months

£783.00

GB Energy Supply

Premium Energy Saver

Variable

£787.00

Extra Energy

Fresh Fixed Price January 2017 v2

Fixed (until January 2017)

£794.00

Extra Energy

Clear Fixed Price January 2017 v1

Fixed (until January 2017)

£801.00

Go Effortless

Domestic Energy December 2015 v1

Fixed for 12 months

£815.51

First Utility

First Fixed March 2017 v2

Fixed (until March 2017)

£816.55

npower

Fixed Energy Online January 2017 (07/01)

Fixed (until January 2017)

£821.00

SSE

SSE 1 Year Fixed v3

Fixed for 12 months

£827.04

Extra Energy

Bright Fixed Price Jan 2017 v1

Fixed (until January 2017)

£830.00

Co-operative Energy

Co-op Online January 2017

Fixed (until January 2017)

£832.00

Prices based on average consumption as measured by Ofgem of 12,500kWh of gas and 3,100kWh of electricity and a customer paying by monthly direct debit including VAT.

Bear in mind the price of your energy will be based on your postcode and so may be more expensive, or even cheaper, than the ones listed.

[Related story: The UK's worst energy companies for customer complaints revealed]

Other things to consider

Fixing your energy bills is a bit of a gamble, much in the same way as fixing your mortgage rate. That’s because prices could come down, which means you end up paying more than you would have done if you were on a variable or even a shorter-term fix.

Having said that, the general trend for gas and electricity prices is to only go one way and that’s upwards, certainly over the long term, although they may fluctuate within a year.

If there’s not much difference between companies, you might want to also consider how good each is when it comes to customer service.

The energy sector as a whole isn’t renowned for being brilliant when it comes to dealing with its customers.

Compare gas and electricity prices and see if you could save big money