The UK tax year ends on 5 April. For most small and medium-sized businesses, that date triggers a frantic scramble to finalise accounts, submit Self Assessment returns, and get MTD submissions through. Once the deadline passes, there is a natural urge to exhale — and leave everything else on the back burner until the new financial year settles in.

But April is actually one of the best times to run a proper IT health check. Your teams have just finished their busiest accounting period, systems are likely up to date with end-of-year patches, and you have a clear window before the summer slowdown. The checklist below covers the five areas most SMEs overlook after tax season — and why fixing them now saves headaches later.

Why April Is the Right Time to Review Your IT Setup

Tax deadlines create a natural inflection point. You have just closed a financial period, your accountants have pulled together a snapshot of your business finances, and many IT changes that were paused during March will now be feasible to implement.

Running an IT review at this point also means you are not waiting for a problem to surface. A missed software update, an ex-employee still holding system access, or unsupported applications that suddenly break — none of these are dramatic until something goes wrong. Catching them in April gives you three full months to fix anything that needs attention before the next busy period arrives.

The Post-Tax Year IT Checklist for SMEs

1. Audit User Access and Leaver Management

When a business pushes through year-end, people take time to process leavers properly. This is a common gap, and it is one of the easiest to fix.

What to do:

• Review all active accounts across Microsoft 365, your CRM, accounting software, and shared drives

• Confirm that every leaver's access has been fully revoked — not just disabled, but removed

• Check that no accounts remain active from temporary contractors or seasonal staff

2. Verify Backup and Recovery Integrity

Tax year end is not the time to discover that your backups stopped working three months ago.

What to do:

• Run a test restore of at least one critical file share and one database

• Check that backup schedules have not been interrupted by licensing changes or expired credentials

• Review your recovery time objectives — if a key system goes down, how long can you realistically afford to wait?

If you do not have a tested backup and recovery process in place, this is the month to build one. Backup and business continuity planning is not a luxury — it is the difference between a minor inconvenience and a business-threatening event.

3. Check Patch Management and Software Versions

End-of-year software updates often bring critical security patches that get deferred during busy periods. Take time to review your patch management schedule to ensure it is active and actively monitoring current threats.

4. Review Cyber Essentials Compliance

Cyber Essentials is becoming a baseline expectation rather than a nice-to-have. Many clients and public sector contracts now require it, and the cost of certification is small compared to the cost of a breach.

If you achieved Cyber Essentials (or Cyber Essentials Plus) last year, your certification is valid for twelve months. April is the moment to check whether you are approaching expiry and whether any changes to your setup since certification need to be documented ahead of the next audit. There is no advantage to waiting until a client request forces your hand.

Our guide on Cyber Essentials and modern security walks through what the scheme actually requires and why it matters more than most SMEs realise.

What to do:

• Check your certification expiry date

• Review any changes to your network, devices, or internet-facing systems since certification

• Book a recertification audit if you are within three months of expiry

5. Standardise Devices and Software Configurations

After a busy tax period, it is common for teams to have adopted workarounds — personal devices for remote access, shared accounts for convenience, or shadow IT applications that slipped through. Standardising back to your approved configurations restores both security and supportability.

What to do:

• Audit which devices are on your network and confirm they are managed by your IT system

• Ensure software configurations match your approved baseline

• Remove any shadow IT applications that have become permanent

Standardisation is not about rigidity — it is about predictability.

Common IT Gaps SMEs Miss After Tax Year End

The gaps above tend to compound quietly. A leaver's access that was never revoked, a backup that stopped working after a password expiry, an unsupported application that suddenly breaks when a key user needs it — none of these are dramatic until something goes wrong.

What makes them particularly frustrating for SMEs is that they are entirely preventable. They do not require expensive technology or specialist knowledge to fix. They require a structured review at a time when the business has the bandwidth to conduct one.

If you do not have an IT team to delegate this to, a managed support partner can run these checks as part of a regular review cycle — which is the point at which gaps like these stop appearing on your radar entirely. Managed IT support in Sussex is built around exactly this kind of proactive approach, rather than reacting to problems after they have caused disruption.

How Should SMEs Use This Checklist?

You do not need to complete every item in one sitting. The checklist is designed to be worked through over a two-to-three-week window, which fits comfortably around the post-tax-season period.

Start with user access and leaver management — this is the fastest win and often reveals the most immediate risk. Then move to backup verification, which requires scheduling a test restore and may surface issues you did not know existed. The remaining items can be tackled in parallel as your team settles back into their normal workload.

If any item on this checklist feels like it would take more time than you can spare, that is exactly when a managed support partner becomes useful. They handle the routine reviews so you can focus on running your business.

Frequently Asked Questions

When exactly does the UK tax year end?

The UK tax year ends on 5 April each year. For the current cycle, that is 5 April 2026. Online Self Assessment returns are typically due by 31 January for the previous tax year, but many SMEs still use this period to finalise accounts and prepare management information.

Can I run an IT audit myself or do I need a professional?

You can start with the checklist items above — particularly user access reviews and patch checks — without external help. For backup testing, compliance verification, and deeper infrastructure reviews, having a professional partner involved tends to produce more reliable results and helps you avoid missing things you do not know to look for.

How long should this checklist take to complete?

A thorough review of all five areas typically takes between two and four hours of focused work, spread over a couple of weeks. If you already have good documentation and monitoring in place, it will be on the faster end. If your systems are largely unmanaged, allow more time — or bring in support.

What happens if I find problems during the review?

Document what you find, prioritise by risk level, and create a remediation plan. Critical issues like active leaver accounts or failed backups should be addressed immediately. Lower-priority items like legacy software can be scheduled for the next quarter.

Get Ahead Before Summer

Tax season is over. Your accounts are submitted. The natural instinct is to let your IT systems run themselves for a while. But the issues that surface during an April review are preventable — and fixing them now means you enter the summer with confidence rather than worry.

If you want a second pair of eyes on your IT estate, book a free Security Triage Call. It takes 20 to 30 minutes and gives you a clear picture of where your systems stand.