Bidmio — ERP for trades, construction and service
    For UK sole traders and small firms

    From shoebox to sorted: records, deadlines and your accountant.

    Receipts in the van, invoices in three inboxes and a phone call to say September is missing. It isn't your fault, and it isn't your accountant's. What's broken is the route the paperwork takes.

    Below are the deadlines, record periods and penalties from gov.uk and legislation.gov.uk, each with a link so you can check it yourself. HMRC and Companies House rules apply across the UK.

    Checked on against gov.uk and legislation.gov.uk. Written for England and Wales: HMRC’s tax and CIS rules apply across the UK, and where we checked that a law does not reach Scotland or Northern Ireland, we say so.

    Where it goes wrong

    You know the routine. Receipts from the merchant end up in the van, in a jacket pocket or in the door pocket. Invoices arrive by email, on paper and as a photo on WhatsApp. At the end of the quarter it all goes to your accountant in one carrier bag.

    Then the phone rings. A receipt from September is missing, a supplier invoice, a bank statement. You're on site with no time to look, and three weeks later you can't remember which job that receipt was for.

    Nobody is doing anything wrong. You do the jobs, your accountant does the books, and you both have deadlines. What's broken is the route the paperwork takes: on paper, late and all at once.

    How long do you have to keep records?

    Sole traders must keep their records for at least 5 years after the 31 January submission deadline of the tax year they relate to[1]. Limited companies keep them for 6 years from the end of the financial year[2]. Records for VAT are kept for at least 6 years[3].

    • Sole trader: gov.uk's own example is a 2022 to 2023 return sent by 31 January 2024, whose records must be kept until at least the end of January 2029[1].
    • Penalty for a sole trader: failing to keep and preserve the records can mean a penalty of up to £3,000 (Taxes Management Act 1970, section 12B(5))[4].
    • Limited company: if you don't keep accounting records, HMRC can fine the company £3,000 or you can be disqualified as a director[2].
    • CIS contractors: CIS records are kept for at least 3 years after the end of the tax year they relate to[5].

    Self Assessment: the dates that run your year

    If you need a tax return for the first time, tell HMRC by 5 October after the tax year. A paper return must reach HMRC by 31 October, an online return by 31 January, and the tax must be paid by 31 January too. If you make payments on account, the second one is due by 31 July[6].

    Late returns have fixed penalties, as gov.uk lists them[7]:

    • Straight away: £100[7].
    • After 3 months: £10 a day, up to £900[7].
    • After 6 months: 5% of the tax due or £300, whichever is greater[7].
    • After 12 months: another 5% or £300, whichever is greater[7].
    • Paying late: 5% of the unpaid tax at 30 days, 6 months and 12 months, plus interest[7].

    Making Tax Digital for Income Tax: are you in?

    You must use Making Tax Digital for Income Tax if you're a sole trader or landlord registered for Self Assessment and your qualifying income is over the threshold for the year[8]. Qualifying income is your income from self-employment and property before expenses, in other words your turnover[9].

    • Over £50,000 in 2024 to 2025: you should have used it from 6 April 2026[8].
    • Over £30,000 in 2025 to 2026: from 6 April 2027[8].
    • Over £20,000 in 2026 to 2027: from 6 April 2028[8].
    • Quarterly updates: due by 7 August, 7 November, 7 February and 7 May[10].
    • Penalties: HMRC will not apply penalty points for late quarterly updates in the 2026 to 2027 tax year. After that, each late update earns a point, and 4 points mean a £200 penalty[10].
    • Partnerships: they will need to use it too; HMRC will set out the timeline later[8].

    If you're VAT-registered, Making Tax Digital for VAT already applies: all VAT-registered businesses should now be signed up[11]. Either way you need compatible software, and your accountant can tell you which one they work with.

    CIS: the monthly return if you pay subbies

    If you pay subcontractors for construction work, you're a CIS contractor, and the return is monthly. It must reach HMRC within 14 days of the end of the tax month, which runs from the 6th to the 5th, so by the 19th[5].

    • Paying HMRC: the deductions are due by the 19th, or by the 22nd if you pay electronically[5].
    • Nil returns are back: from 6 April 2026 a mainstream contractor that paid no subcontractors in a month must file a nil return or tell HMRC about a period of inactivity[5].
    • Late returns: £100 the day after the deadline, another £200 after 2 months, then the greater of £300 or 5% of the deductions on the return after 6 months and again after 12 months[5].
    • Your subbies: each one you deducted from gets a payment and deduction statement by the 19th[5].

    If you run a limited company

    A company pays its Corporation Tax 9 months and 1 day after the end of its accounting period[12], and the Company Tax Return is due 12 months after the end of the period[13]. Accounts that reach Companies House late cost a private limited company[14]:

    • Up to 1 month late: £150[14].
    • 1 to 3 months: £375[14].
    • 3 to 6 months: £750[14].
    • More than 6 months: £1,500, and the penalty is doubled if the accounts are late 2 years in a row[14].

    Letting your accountant deal with HMRC

    Your accountant needs HMRC's authorisation for each tax they handle, and the route depends on the tax[15]:

    • Making Tax Digital for Income Tax and VAT: the “digital handshake”, a request your accountant starts online. There is no paper form for these[15].
    • Self Assessment and Corporation Tax: Online Agent Authorisation, or the paper form 64-8[15].
    • PAYE: Online Agent Authorisation or your business tax account, or form 64-8[15].
    • CIS: Online Agent Authorisation or your business tax account; there is no paper route[15].

    Changing accountant without losing a quarter

    You can remove an agent's authorisation online in your business tax account[16]. For VAT and employer PAYE, if you also want to stop them dealing with HMRC for you by phone or in writing, you must write to HMRC and phone it as well[16]. Your new accountant then gets authorised in the ways above[15].

    HMRC's part is only the authorisation. Ask your new accountant what they need from you and from the old one, and agree a date when they take over, ideally the start of a quarter.

    E-invoicing is coming: from 2029

    The government has decided that all VAT invoices must be issued as e-invoices from 2029. That covers invoices to businesses and the public sector, not to private customers[17]. It says it will publish a roadmap for the change at Budget 2026[17]. Until then, nothing changes for your invoices.

    What actually fixes it

    Not more phone calls. A different route for the paperwork:

    • Receipts on the day: photograph them at the counter and put them on the job, so nothing sits in the van.
    • One place for both of you: your accountant sees the documents themselves instead of waiting for the bag.
    • A fixed cut-off: agree a day each month when everything for the month is in.
    • Your own checklist: the duties and rights check lists the deadlines that apply to you.

    What Bidmio can and can't do about it

    Bidmio doesn't change the law or the deadlines. But the paperwork is in one place from day one, and your accountant can see it without waiting for the bag.

    • Photograph a receipt and Bidmio reads the amount, date and supplier. It stays on the job it was bought for, and your team can do the same from their phones.
    • Invite your accountant or bookkeeper as an external user, for the companies you choose. They see the invoices, receipts and bank matches themselves, and you remove the access in one click.
    • Invoices in pounds with VAT, and a list of which ones are paid and which are overdue.
    • Import your bank statement and payments are matched to invoices.
    • Export invoices and expenses to CSV for any period, ready for your accountant's own software.

    Honestly: Bidmio files nothing with HMRC. It is not Making Tax Digital software, it does no CIS or UK payroll, it doesn't connect to Xero, QuickBooks, Sage or FreeAgent, and it doesn't send UK e-invoices. Your accountant keeps the books and deals with HMRC.

    Try it free for 14 daysBook a call

    Are you an accountant? See what you get as your client's accountant

    Your accountant doesn't need more phone calls. They need the paperwork on time and in one place.

    Sources

    Every figure in this article has the number of its source in square brackets. We last checked every link on 24 October 2026. Figures are given exactly as the source states them.

    1. [1]Business records if you're self-employed: how long to keep your records. GOV.UK, 2026.
    2. [2]Running a limited company: company and accounting records. GOV.UK, 2026.
    3. [3]Record keeping for VAT (VAT Notice 700/21). HM Revenue & Customs, 2026.
    4. [4]Taxes Management Act 1970, section 12B (records to be kept). legislation.gov.uk, 1970.
    5. [5]Construction Industry Scheme: a guide for contractors and subcontractors (CIS 340). HM Revenue & Customs, 2026.
    6. [6]Self Assessment tax returns: deadlines. GOV.UK, 2026.
    7. [7]Self Assessment tax returns: penalties. GOV.UK, 2026.
    8. [8]Find out if and when you need to use Making Tax Digital for Income Tax. HM Revenue & Customs, 2026.
    9. [9]Work out your qualifying income for Making Tax Digital for Income Tax. HM Revenue & Customs, 2026.
    10. [10]Use Making Tax Digital for Income Tax: send quarterly updates. HM Revenue & Customs, 2026.
    11. [11]Charge, reclaim and record VAT (Making Tax Digital for VAT). GOV.UK, 2026.
    12. [12]Pay your Corporation Tax bill. GOV.UK, 2026.
    13. [13]Company Tax Returns. GOV.UK, 2026.
    14. [14]Prepare annual accounts for a private limited company: penalties for late filing. GOV.UK, 2026.
    15. [15]How to get authorised to act as a tax agent on behalf of your clients. HM Revenue & Customs, 2026.
    16. [16]Change or remove your tax agent's authorisation. HM Revenue & Customs, 2026.
    17. [17]Promoting electronic invoicing across UK businesses and the public sector: consultation response. HM Revenue & Customs and Department for Business and Trade, 2025.