How should accountants post about tax deadlines? Four posts, one action each

The short answer

Post about each deadline early, in a planned sequence, with one clear action in every post. For any deadline that matters to your clients, that means four posts: an awareness post well ahead, a "one action" post, a final-week nudge and a calm post the morning after. Write and schedule all four in one sitting, months before busy season, so nobody has to write them in January.

Deadline posts are the one kind of content every client finds useful. They are timely, they affect real money, and they give the firm a natural reason to say "send it to us". Done well, they also cut the number of panicked phone calls in the last week.

Why most deadline posts are wasted

Most firms do post about deadlines. The posts just do little, for three reasons.

• They land too late. A first reminder in the last week of January reaches people when it is already too late to gather records calmly. It mostly adds to the rush the firm is trying to avoid.
• They read as a telling-off."Don't leave it to the last minute!" and a list of fines makes the reader feel scolded. People who are behind already feel bad about it, so they scroll past.
• They ask for nothing specific."The deadline is coming" is information, not an action. The reader nods and does nothing, because the post never told them what to do today.

The fix for all three is the same: plan the posts before the season, and give each one a single, specific job.

The four-post sequence for any deadline

Use four posts per major deadline, each with a different job. The timings below suit a big deadline like Self Assessment. For a smaller one, squeeze them closer together or drop the first.

1. The far-out awareness post (two to three months ahead)

Name the deadline, say who it applies to, and ask for one early step, usually "send us your records by" a date you choose. Your own cut-off date matters more than HMRC's here, because it is the one that protects your January. This is the post that does the most good, and the one most firms skip.

2. The "one action" post (four to six weeks ahead)

Pick a single thing the reader can do this week and make the whole post about it. Good choices are finding a missing document, checking they can log in to their HMRC online account, or deciding how they will pay. If you have several actions to share, make several posts, a week or so apart, not one long list.

3. The final-week nudge

Short, calm and practical. Give the date and time, say what still counts as on time, and tell people what to do if they are behind, including whether you can still help. Do not pile on warnings. People reading this post in the last week already know they are late.

4. The morning-after "still not filed" post

Almost no firm posts this, which is why it works. On the first working day after the deadline, some people have missed it and are worried. A plain post that says what happens now, what to do first, and that you can help makes the firm look steady and kind at the moment people are most likely to look for an accountant.

Worked example: Self Assessment, January 2027

Here is the sequence for the next Self Assessment deadline, with every date taken from GOV.UK's Self Assessment deadlines page. Online returns for the 2025 to 2026 tax year must be submitted by 11:59pm on 31 January 2027, and the tax owed must be paid by the same time. Paper returns must reach HMRC by 11:59pm on 31 October 2026. Anyone who wants their bill collected through their tax code must submit online by 11:59pm on 30 December 2026.

• Early November (awareness). The 31 January date, who it is for, and your own date for receiving records.
• Early to mid December (one action). The 30 December tax code date. GOV.UK says anyone who wants to pay their bill through their tax code must submit online by then, so name the date and suggest they ask you whether it applies to them.
• Early January (one action). How to pay: GOV.UK's paying your Self Assessment bill page explains that 31 January is also when the first payment on account is due for those who make them, with a second on 31 July. It also says some payment methods take several working days.
• Week of 25 January (final-week nudge). 31 January 2027 falls on a Sunday, so post earlier in the week and say plainly what your office hours are that weekend.
• Monday 1 February (morning after). What to do if you missed it.

Three of those posts, written out, might look like this.

The penalty in the last post is exactly as GOV.UK's Self Assessment penaltiespage states it: an initial £100 penalty for a late return, then further penalties after 3, 6 and 12 months, and separate penalties of 5% of unpaid tax at 30 days, 6 months and 12 months. The instalment line comes from GOV.UK's page on paying in instalments, which says you may be able to set up a payment plan and that HMRC checks whether it is affordable. Change the dates, the cut-off and the tone to suit your firm, and check every figure against GOV.UK before it goes out.

What each post should and should not say

Every deadline post should pass the same short test. These rules are what separate a reminder people act on from one they scroll past.

Do

• Ask for one action. Send records, log in, choose how to pay, call us. One per post.
• Use plain language."Your tax return and your tax bill are both due by 31 January", not "the filing and balancing payment deadline".
• Give the exact date and time. Include the time where GOV.UK gives one, such as 11:59pm, and the day of the week.
• Say who it applies to."If you are self-employed or rent out a property" helps the right people stop scrolling.
• Link to the GOV.UK page. It backs up the date and lets readers check for themselves.

Do not

• Threaten penalties you have not checked. If you mention a penalty, state it exactly as GOV.UK does. Never round up, guess, or imply a fine applies when it may not.
• Share anything about a client. No stories about a client who filed at 11:58pm, even without a name, if the details could identify them.
• Scold."You know who you are" and lots of exclamation marks make people who are behind feel worse, not more likely to call you.
• Promise what you cannot deliver.Do not say "we can still file for you" in the final week unless you really can take on new work.
• Reuse last year's post unchecked. The tax year in the post changes every year, and dates and rules sometimes do too.

The same rules apply to the email reminders many firms send alongside their posts. Our guide to email marketing for accountantscovers how to write a deadline email that clients act on. And whatever you publish, check your own professional body's guidance on advertising and client confidentiality, whether that is ICAEW, ACCA, AAT, ICB or another.

Write and schedule the whole sequence in one sitting

The best time to write January's posts is October or November. Block out an hour, open the GOV.UK page for each deadline, and write all four posts for each one. Then schedule them, so they go out on their own while the team is busy with returns.

• Check every date against the source. Have the GOV.UK page open while you write, and get a second person to check the dates before you schedule.
• Pick your own cut-off date first. The awareness post depends on it, and it should match what your team can actually handle.
• Leave room for news. If a date or rule changes, edit the scheduled posts. That is why every post links to GOV.UK and names the source.
• Decide who answers replies. Deadline posts get questions. Agree who replies, and how fast, before the first one goes out.

If writing even one hour of posts is hard to fit in, this is where a tool helps. Pillr reads your firm's website, drafts posts in your firm's voice, including deadline reminders, and schedules each one once you have approved it. A partner can check and approve the whole deadline sequence in one sitting, then leave it to publish. The plans are on the pricing page, and you can see what it would draft for your firm by pasting your website address on the home page. Check every date and figure in the drafts against GOV.UK before you approve them, as you would with posts you wrote yourself.

Using the same pattern for other deadlines

The four-post sequence works for any deadline your clients have to act on, such as VAT returns, payroll year end, company accounts or the 31 July payment on account. Scale it to the deadline.

• Big, once-a-year deadlines that affect most clients: all four posts.
• Deadlines that affect only some clients: one awareness post and one final-week nudge, each saying clearly who it applies to.
• Frequent deadlines, such as quarterly VAT: one short reminder each time, or a single post explaining how the cycle works, rather than four posts every quarter.

For each one, take the dates from the GOV.UK page for that deadline in the year you are posting, not from memory or an old post. For more ideas on what else to post through the year, see our list of social media post ideas for accountants.

This guide is general information, not advice on your own circumstances. Check your own professional body's guidance before you publish anything about your services.

Questions accountants ask about deadline posts