Once the Self Assessment deadline passes, there’s often a collective sigh of relief.

The return is filed.
The payment has gone out.
January is finally behind us.

But in reality, January doesn’t finish everything, it often just brings a few things into view.

Every year, we speak to business owners in February who feel like they’ve “sorted” their tax, only to discover there are still a few loose ends quietly sitting in the background.

Here are some of the most common ones we see 👇

This is probably the biggest one.

Many people assume that once January’s bill is paid, they’re done for the year. But for a lot of self-employed individuals and landlords, payments on account mean there’s more to come.

That often includes:

• a second payment due in July 📅

• future liabilities already showing on HMRC statements

• confusion over why tax is appearing “again”

Nothing has gone wrong, it’s just the system working as intended. But it’s easy to forget about if it isn’t planned for.

January tax bills often highlight cashflow issues that were already there, they just weren’t obvious yet.

We regularly see businesses where:

• profits look healthy on paper

• but cash balances feel tight

• tax payments rely on last-minute juggling

Once the deadline passes, it’s tempting to move on quickly. But February is often the best time to pause and ask whether cashflow is actually working as it should.

Another common theme is bookkeeping that’s technically up to date, but not especially useful.

After January, many business owners are left with:

• figures that helped file a return ✔️

• but don’t really help with decision-making ❌

If the numbers only get attention once a year, it’s easy for small issues to build up quietly in the background.

January filing often triggers:

• statements

• confirmations

• reminders

• future payment notices

These letters aren’t always urgent, but they are often misunderstood.

We see plenty of worry caused by letters that look alarming at first glance, but simply outline what’s coming later in the year.

Understanding which letters matter (and which don’t) makes a big difference to stress levels.

January has a habit of becoming something to get through, rather than learn from.

Once it’s over, many people understandably want to:

• park tax for a while

• focus on running the business

• not think about deadlines again just yet

But the most useful insight January gives isn’t about the return, it’s about how the year unfolded leading up to it.

February is often where the real opportunity lies.

It’s a chance to:

• reflect calmly

• spot patterns before they repeat

• make small changes that reduce pressure next time

January might be the deadline, but February is where better systems usually begin.

If January felt harder than expected, it’s rarely down to one big mistake.

More often, it’s the result of things that were assumed to be “dealt with”, but weren’t quite finished yet.

Taking a little time in February to review what January revealed can make the rest of the year far more predictable and far less stressful.

At Llewellyns, we believe the best tax outcomes come from understanding what’s happening between the deadlines, not just racing to meet them.