Miss one HMRC deadline and it can feel like you have set fire to your profit. If your business turns over more than five hundred thousand, you cannot afford that. So let’s make your tax calendar foolproof. In this guide, you will get the recurring dates that keep your business safe, plus simple systems to stop penalties before they start.
Your Monthly Non-Negotiables
These are the heartbeat tasks that repeat every month. Treat them like rent. They always fall due.
PAYE and National Insurance payments
If you pay manually, the deadline is the 19th of the following month.
If you pay by Direct Debit, HMRC collects on the 22nd.
A smart cash move is to hold your PAYE and NIC money in a higher interest savings account, then transfer it to your current account the day before collection. It is free interest for doing nothing more than planning ahead.
RTI submissions for payroll
Your RTI must be submitted before you pay your team. If you run payroll on the last Friday of the month, make sure RTI has already gone. Your payroll software should make this quick.
CIS returns and payments
If you are in construction and operate CIS, submit your CIS return by the 19th of the following month and pay on time. Repeated misses rack up one hundred pound penalties that add up fast. Bank feeds and tidy ledgers make this easy. Even if your records are not perfect, you can often reconstruct from net payments and gross them up accurately.
VAT: Quarterly rhythm, monthly habits
Most businesses file VAT quarterly. Your return and payment are due one month and seven days after the VAT period end. For example, a quarter ending on 31 December is due by 7 February. The truth is you do not need to wait that long. With bank feeds and invoice capture, you can have a clear picture within a week or two of quarter end. Keep a running estimate each month, park the cash in savings, and sweep it back the day before HMRC collects. Again, that is free interest and fewer surprises.
Fixed Annual Tax Dates You Should Memorise
These dates arrive like clockwork every year. Add them once, and you are set.
5 April
The UK tax year ends. Make sure your payroll software has the new thresholds for the incoming year. Pull in updated data from your provider if needed.6 April
New tax year starts. Refresh tax codes for team members where HMRC has issued changes. This captures adjustments for prior year underpayments or benefits in kind.31 May
Deadline to provide P60s to all employees. Most payroll systems have portals that make distribution quick. If this feels hard, it is a sign your system needs attention.6 July
Deadline to submit P11Ds for benefits in kind, such as company car, fuel and health insurance. These drive Class 1A National Insurance for the employer.22 July
Deadline to pay Class 1A National Insurance. If paying manually, it is the 19th.31 October
Paper Self Assessment filing deadline. Some people still file on paper for their own reasons. If that is you, ring this date in red.31 January
Online Self Assessment filing deadline and payment of any balancing liability plus the first payment on account, if due. Do not leave this until the last week. Finish early and remove the stress.31 July
Second payment on account for the tax year. The first year you face payments on account can feel like a punch in the face because you pay last year’s balance and next year’s first instalment at the same time. Once you are in the rhythm, six monthly payments smooth your cash flow. Use savings pots to earn interest while you wait.
Limited Company Anchor Dates
These are the company-specific milestones that keep you compliant and visible. Miss them and the consequences can be serious.
Company accounts filing at Companies House
You have nine months after your year-end to file your accounts. For a 31 December year-end, that is 30 September of the following year. In practice, aim to complete within three months, so you are not scrambling.
Corporation Tax payment
Your Corporation Tax must be paid within nine months after year end. Reconcile the payment to your calculated liability and do not guess.
CT600 filing deadline
Your company tax return is due twelve months after the year-end. It always feels odd that payment is due before the return, so the best habit is to calculate the tax, file the CT600 and move on.
Confirmation statement
File your confirmation statement annually, usually linked to your company formation month. You have fourteen days from the statement date to file. Forgetting this is a common reason for accidental company dissolutions. There is rarely a large penalty for lateness, but the risk to your company status is not worth it.
Make Your Calendar Foolproof
Great businesses do not rely on memory. They rely on systems. Here are three that work.
One master calendar for tax
Put every deadline in a single calendar. Add reminder layers at fourteen days, seven days and one day before each due date. This prevents last minute scrambles and spreads the workload.Two internal owners
One person is responsible. Another person is watching their back. Illness, holidays and emergencies happen. Dual ownership keeps the process moving.Direct Debit plus sweep from savings
Wherever possible, pay HMRC by Direct Debit so things happen automatically. Park the cash in a savings account while you wait, then sweep it to your current account the day before the debit. It is simple, disciplined and earns interest on money that would otherwise sit idle.
Penalties are profit leaks
You work too hard to let profit drip away through avoidable fines and interest. Penalties waste cash, chew up time and can damage credit. Close the leaks with dates, owners and automation. It really is that straightforward.
Your next step
If you want these dates mapped to your business with a ready to use calendar and simple cash flow plan, book a short Tax Chat with me. We will look at your setup, fill the gaps and keep you safe from needless penalties. There is no pushy sales pitch. Just clear answers and a plan that works for a company in the five hundred thousand to two million range.
