Tax Diary: June to July 2023 Deadlines That May Still Matter

This tax diary highlights key tax deadlines that fell between June and July 2023 and is relevant for taxpayers who want to check whether any obligations from that period were missed.

Although these dates have passed, unresolved filing or payment issues linked to them can still result in penalties, interest, or HMRC follow-up action.

Key Tax and Payroll Deadlines for June and July 2023

1 June 2023 – Due date for corporation tax due for the year ended 31 August 2022.

19 June 2023 – PAYE and NIC deductions due for month ended 5 June 2023. (If you pay your tax electronically the due date is 22 June 2023).

19 June 2023 – Filing deadline for the CIS300 monthly return for the month ended 5 June 2023.

19 June 2023 – CIS tax deducted for the month ended 5 June 2023 is payable by today.

1 July 2023 – Due date for corporation tax due for the year ended 30 September 2022.

6 July 2023 – Complete and submit forms P11D return of benefits and expenses and P11D(b) return of Class 1A NICs.

19 July 2023 – Pay Class 1A NICs (by the 22 July 2023 if paid electronically).

19 July 2023 – PAYE and NIC deductions due for month ended 5 July 2023. (If you pay your tax electronically the due date is 22 July 2023).

19 July 2023 – Filing deadline for the CIS300 monthly return for the month ended 5 July 2023.

19 July 2023 – CIS tax deducted for the month ended 5 July 2023 is payable by today.

Why Past Tax Diary Deadlines Are Still Relevant

Tax deadlines do not become irrelevant simply because time has passed. Where a return was not submitted or a payment was made late, the issue can remain open until it is resolved.

This means June and July 2023 deadlines may still affect you today if HMRC considers an obligation outstanding, something a tax specialist in London would typically identify when reviewing historic compliance.

Common Obligations Around June and July

Deadlines during this period often relate to:

• Self Assessment filing and payment obligations
• VAT return submissions and payments
• PAYE and National Insurance reporting and payments
• Mid-year compliance and reporting requirements

Which obligations applied will depend on your circumstances, such as whether you were self-employed, an employer, or VAT-registered.

What Happens If a Deadline Was Missed?

If a tax deadline from June or July 2023 was missed, HMRC may have issued penalties or charged interest.

In some cases, penalties increase over time until the return is filed or the payment is made. Even where no immediate penalty was raised, HMRC may still pursue the issue later, often after a later review by a tax advisor in London or during an HMRC compliance check.

Why It Is Worth Reviewing Now

Some taxpayers assume older deadlines no longer matter. In practice, unresolved issues often resurface through HMRC reminders, statements of account, or compliance checks.

Reviewing whether all obligations from June to July 2023 were met can help avoid unexpected demands or enforcement action.

HMRC Guidance on Late Tax Deadlines

HMRC provides guidance on late filing, late payment, and the penalties and interest that may apply on
GOV.UK.

Did You Miss Any June or July 2023 Deadlines?

Whether any action is required now will depend on which obligations applied to you at the time and whether they were handled correctly. For individuals and businesses in Fulham Broadway and nearby areas such as Eel Brook Common and Fulham Reach, CIGMA Accounting can review the position and confirm whether anything remains outstanding or needs to be addressed.