Skip to Content
Skip to Main Menu

Tax Deadlines

Self assessment tax deadlines provide a clear framework for compliance, whether you’re self-employed, retired, or receive additional income in employment. It’s important to prepare well ahead of these key dates, however, to allow for any complications or misunderstandings to be rectified, and prevent HMRC penalties being applied.

The tax year 2017-18 started on 6th April 2017 and ends on 5th April 2018, so what are the deadlines and key dates for 2017/18?

When is the self assessment tax deadline?

  • The registration deadline for self assessment is 5th October 2018
  • Paper tax returns are due by midnight on 31st October 2018
  • If your tax liability is less than £3,000 for wages or pension income, and you wish HMRC to collect it through your tax code, the deadline for online submissions is 30th December 2018
  • For online tax returns, the submission deadline is midnight on 31st January 2019
  • The deadline to pay tax for 2017/18 (balancing payment plus first payment on account for 2018/19) is midnight on 31st January 2019

 You should be aware that some payment methods take longer than others to clear with HMRC. For example, payments made using online or telephone banking via the Faster Payments system should be received on the same day or the following day.

BACS payments and direct debits, on the other hand, generally take three working days, whereas cheques sent through the post could take five working days or more to clear.

Are there any potential deadline extensions?

HMRC may consider extending their self assessment deadlines in some circumstances. If you suffered an unexpected illness, or a partner or close relative died, for example, they should take this into account and allow an extension to the filing deadline.

Instances where you’ve failed to understand their online filing system or haven’t registered on time won’t be taken into consideration, however, and will result in a late filing penalty.

Using a paper form rather than filing online

Certain taxpayers may benefit from using a paper tax return rather than filing online for 2017/18. If your tax affairs are relatively straightforward, you may qualify to use a Short Tax Return (SA200). The paper form deadline for the 2017/18 tax year is 31st October 2018.

The Short Tax Return may be appropriate if you’re a pensioner, employed, or are self-employed but have a relatively low turnover. You should retain the usual records, however, to support your figures, as you would with a full tax return.

Landlord tax deadline

New regulations regarding buy-to-let tax and landlord liability mean you need to take extra care with your self assessment tax return in 2017. Although key dates and deadlines are the same as those mentioned earlier, you should ensure your understanding of the tax changes, and how they will impact your calculations and the information provided to HMRC.

It’s advisable to seek professional assistance in this respect if you’re unsure – we can recommend highly experienced professionals in your area who can assist.

Partnership tax deadlines and responsibilities

The deadlines for filing and paying partnership tax are as laid out previously, with any profits being shared according to the partnership agreement. Partners must complete their individual tax returns which also contain pages relating to the partnership.  

Penalties when a 2017 tax deadline is missed

The penalty for missing a self assessment deadline can be severe, and increases the longer the tax return or payment of tax remains outstanding. A fine of £100 is imposed if your tax return in only one day late, and fines can increase up to a total of £900 over several months.

Penalties of 5% are charged from six months onwards, and if you pay late you’ll also be charged 5% of the outstanding tax due. You can make an appeal against these penalties if you feel they’re unwarranted, but again, there is a deadline for doing so.

The deadline for appealing a tax penalty is 30 days from the date on the HMRC notice. If the appeal is successful the penalty will be set aside, or refunded if you’ve already paid, along with any interest due to you.

Handpicked Accountants can help you find trusted accountancy help to ensure your meet all self assessment key dates and deadlines. We’ll provide a number of recommendations for accountants in your area, based on our professional working relationships and knowledge of their working practices. This ensures you receive only the highest levels of service – call one of our team to find out more.

View more on Self-Assessment

David Tattersall
Speak to a Handpicked Expert today

Hi there - I'm David from Handpicked Accountants. If you need help finding the right accountant, simply give me a call. My expertise is in connecting business owners with the very best professional services and I'm on hand to assist you today.

  After 3 months of searching various websites and numerous meetings with an array of accountants we quickly realised we needed someone to help us find a perfect match. Handpicked Accountants took less than 24 hours to find the perfect accountant for our company. Kerry Sharpe Kerry Sharpe Luminex Groundworks - Leeds
  I was looking for an accountant and found one, thanks to Handpicked Accountants. Jeremy Falwell Jeremy Falwell Managing Director - Falwell Finance

Subscribe to the newsletter and receive news, advice and key insights in your inbox every month

By clicking submit you will receive the Handpicked Accountant newsletter. All emails include an unsubscribe link. You may opt-out at any time. See PRIVACY POLICY.

Thanks for subscribing to the newsletter. ×