Six October Money Dates That Could Affect Your Budget

October is unusually busy for household finances, with changes to energy bills, a tax registration deadline, supermarket promotions and Christmas savings deadlines all landing in the same month. None of these dates means you should spend money simply because a deadline exists, but missing the right one could mean paying more or losing an entitlement you intended to use.

This article gives general information rather than personal financial or tax advice. Rules and offers can change, so use the linked official source before acting on a deadline.

What money deadlines are coming up in October?

1st October: the new energy price cap starts

Ofgem’s new energy price cap takes effect on the 1st of October for households on default variable tariffs in England, Scotland and Wales. The typical Direct Debit figure rises to £1,723 a year, with average electricity at 26.32p per kWh and gas at 7.97p per kWh. Your bill isn’t capped at £1,723 because what you pay still depends on how much energy you use.

If you have a smart meter, readings should normally be sent automatically, but taking a photo of the display around the changeover gives you your own record. If you submit readings manually, send them promptly so your supplier can split usage around the old and new rates accurately.

Our energy price cap guide has the unit-rate detail.

5th October: tell HMRC if you need to register for Self Assessment

If you need to complete a tax return for the 2025/26 tax year and you haven’t filed before, HMRC says you must tell it by the 5th of October. The same deadline can apply if you were registered in the past but didn’t need to send a return for 2024/25.

Missing the registration deadline can lead to a penalty, although the tax-return filing deadline comes later.

This is especially relevant to people who started self-employment or a side hustle during the year to the 5th of April 2026. Check whether you actually need to file before registering, because the £1,000 trading allowance and other rules can affect the answer.

Our side hustle tax guide explains that distinction in more detail.

6th October: Sainsbury’s 25% Taste the Difference offer ends

Nectar members can currently save 25% on more than 600 Taste the Difference products at participating Sainsbury’s supermarkets and online, with the promotion ending on the 6th of October. Online delivery costs range from £1 to £9.50 and Click & Collect from 50p to £6, so those charges matter if you are placing a small order mainly for the offer.

A premium item at 25% off can still cost more than a standard own-brand alternative, so check the unit price and only switch up if you actually value the difference. Nectar is required and product availability varies by store.

14th October: last day to earn Asda’s 5p fuel coupon

Asda Rewards customers who spend at least £40 in one qualifying in-store transaction can currently receive a 5p-per-litre fuel coupon in the app. The shopping offer runs until the 14th of October and the coupon can be used on one fuel purchase until the 31st of October at participating Asda-branded filling stations. On a 60-litre fill, 5p per litre is worth £3.

Don’t add items to a basket merely to reach £40 if you weren’t going to buy them anyway. A £3 fuel saving on a 60-litre fill doesn’t make a £10 unnecessary spend worthwhile. It’s also sensible to compare the pump price with nearby stations before deciding where to fill up.

25th October: Tesco Clubcard Christmas Savers closes

Tesco Clubcard Christmas Savers closes for 2026 top-ups at 11.59pm on the 25th of October. The bonus depends on your top-up balance, as shown below. Bonus vouchers are valid for three months, while ordinary Clubcard and top-up vouchers last two years.

If you already intended to spend the money at Tesco, the bonus may be useful. It’s still retailer-locked money rather than cash in a normal savings account, so compare that trade-off before adding a large top-up just for the bonus.

28th October: Autumn Budget

HM Treasury has confirmed that the Autumn Budget will be delivered on Wednesday the 28th of October. Tax, benefits and household-cost measures can be announced at a Budget, but predictions before the statement aren’t confirmed policy. For budgeting purposes, the useful date is the announcement itself and then the implementation date attached to any measure that affects you.

What I would do now

Put only the dates that apply to you into your calendar and attach the action to the date, such as submit a meter reading, check whether Self Assessment registration is needed or make a planned Christmas Saver top-up. Retail deadlines are optional opportunities, while tax and bill dates may have a more direct financial effect. That distinction stops a useful reminder turning into pressure to spend.

Frequently asked questions

When is the new energy price cap?

The next energy price cap starts on the 1st of October 2026 and runs to the 31st of December. It affects default variable tariffs, not an existing fixed tariff rate.

What happens if I miss the 5 October Self Assessment registration deadline?

HMRC says you could receive a penalty if you tell it after the 5th of October 2026 when you were required to register. You should still register as soon as possible rather than waiting for the later filing deadline.

When does Tesco Christmas Savers close?

The final opt-in and top-up deadline for Tesco Clubcard Christmas Savers 2026 is 11.59pm on the 25th of October. The bonus depends on your top-up balance at that point.

When is the Autumn Budget?

HM Treasury has confirmed the Autumn Budget will take place on Wednesday the 28th of October 2026. Measures aren’t final until they are announced and published.