If you wait until after 5 April, many opportunities disappear, and you are left with damage control. This checklist is built for company directors, self employed people, and landlords who want practical actions, not theory, with a strong focus on what moves the needle before the deadline.
Total Books Accountants Ltd supports UK businesses and landlords with tax planning, Self Assessment, Let Property Campaign disclosures, VAT, payroll, and business advisory from our offices in Cardiff, Newport and Bristol, with UK nationwide delivery through our secure virtual service platform. You can start with a free 15-minute consultancy call to confirm what actions make sense for your income mix and deadlines.
Key takeaways
- March is your final window to use annual allowances before they reset on 6 April.
- Directors can still optimise salary, dividends, pension contributions, and timing of expenses before year end.
- Sole traders can still reduce taxable profit with allowable expenses, capital allowances, pension payments, and timing of invoices and purchases.
- Landlords can still check property profit, allowable costs, finance cost treatment, and ownership splits, and plan disclosures if anything is missing.
- Couples planning can unlock unused allowances, especially where one partner has lower income.
- Record clean-up now reduces HMRC enquiry risk, late filing penalties, and surprise tax bills later.
- A short tax planning review in March often saves more than it costs because it prevents irreversible after-5-April mistakes.
Why March is the most valuable month for UK tax planning
March is valuable because you still control timing, and timing controls tax outcomes.
Many tax rules run on an annual basis, so small decisions made before 5 April can change the tax you pay for the whole year. After 5 April, those decisions often become locked in.
March is also the month where HMRC risk increases if your paperwork is messy.
If your records are incomplete, you are more likely to file late, estimate figures, or miss reliefs. Cleaning up in March gives you accuracy and confidence before deadlines.
What should you do first in March before thinking about “saving tax”?
You should map your income sources and your likely tax band for the year, because most planning depends on that.
Tax planning without knowing your income mix is guesswork. Directors often have salary plus dividends. Sole traders have trading profit. Landlords have rental profit and sometimes capital gains. High earners can lose allowances if total income is high. You need a quick “income picture” before making moves.
You should also check what you have already used.
If you have already paid into a pension, already used your dividend allowance, or already sold assets with gains, your remaining headroom changes. A simple year-end summary prevents duplicate actions.
The March checklist for directors of limited companies
Directors can reduce tax in March by reviewing salary, dividends, pension contributions, company expenses, and profit extraction timing before 5 April.
The biggest director mistakes are leaving dividends to the last minute, forgetting pension opportunities, and mixing personal and business spending without clear records.
Are you paying yourself a sensible director salary?
You should confirm your director salary level aligns with your tax strategy and NI position before the year ends.
A salary that is too low can waste personal allowance and affect state benefit and pension qualifying years. A salary that is too high can create unnecessary National Insurance. The right level depends on your wider income, other employments, and benefits.
Actions to take in March:
- Check total salary paid so far in the tax year
- Confirm whether an additional salary payment before 5 April helps or harms your tax position
- Confirm payroll submissions are up to date and correctly reported
Have you taken dividends in the right amounts and at the right times?
You should confirm dividends were declared properly and timed to avoid unnecessary higher-rate dividend tax.
Dividends must be supported by profit and correctly documented, and timing matters because dividends taken before 5 April fall into this year’s tax bands.
Actions to take in March:
- Confirm company distributable reserves
- Confirm dividend vouchers and minutes exist
- Check whether taking dividends now will push you into higher-rate bands
- Consider splitting dividends across tax years where appropriate
Can your company make an employer pension contribution before 5 April?
You should consider employer pension contributions because they can be one of the most efficient director tax planning tools when structured correctly.
Employer contributions can reduce company taxable profits and can avoid personal tax that dividends might trigger, subject to pension rules and allowances.
Actions to take in March:
- Check your pension contribution position and any carry-forward opportunity
- Confirm company cash flow can support the payment
- Ensure the contribution is made and recorded correctly before 5 April
Have you claimed all allowable company expenses and benefits properly?
You should review company expenses because missed claims increase profit and therefore increase corporation tax.
At the same time, incorrectly claimed expenses increase HMRC risk. The goal is accuracy, not aggression.
Actions to take in March:
- Review business mileage, travel, and subsistence records
- Review home working claims where relevant
- Review professional subscriptions, training, and software
- Check reimbursements are supported with receipts and proper records
Are you planning for corporation tax and personal tax together?
You should align company year end planning with the personal tax year where possible because cash and tax do not sit in separate boxes.
A director can accidentally reduce company profit but increase personal tax, or vice versa. March planning should balance both.
Actions to take in March:
- Forecast company profit and corporation tax
- Forecast personal income tax and NIC
- Check cash reserves for future tax payments
- Decide what extraction route best fits your total position
Do you need to fix your director loan account before year end?
You should review your director loan account because overdrawn balances can create tax charges and compliance risk.
A loan account issue often appears when directors take money without clear salary or dividend treatment.
Actions to take in March:
- Check if the director loan account is overdrawn
- Confirm whether repayment or dividend reclassification is appropriate
- Avoid last-minute transactions that create messy records
The March checklist for sole traders and self employed people
Sole traders can reduce tax in March by ensuring allowable expenses are claimed, invoices and costs are timed sensibly, and pension contributions are planned before 5 April.
The most common problem is underclaiming allowable costs or claiming costs without evidence, so March is about clean records.
Have you captured every allowable expense with evidence?
You should review your allowable expenses because missing costs increases taxable profit.
Common categories include tools, equipment, vehicle costs, phone and internet, professional fees, insurance, marketing, and home office costs, depending on your trade.
Actions to take in March:
- Export bank transactions and reconcile to receipts
- Check subscription payments such as software and licences
- Review travel logs and mileage records
- Confirm any cash spending is supported
Should you bring forward key purchases before 5 April?
You should consider timing of purchases because buying business equipment before 5 April can reduce taxable profit for the year, subject to the correct tax treatment.
This is often relevant for tools, IT equipment, furniture, and other business assets.
Actions to take in March:
- Identify essential purchases you were going to make anyway
- Confirm whether the purchase is revenue or capital in nature
- Keep invoices dated and paid clearly
Should you chase invoices or delay billing?
You should consider invoice timing because invoicing dates affect taxable profit for some businesses depending on accounting basis.
This is not about hiding income. It is about managing timing lawfully within your accounting method.
Actions to take in March:
- Confirm whether you use cash basis or traditional accrual accounting
- Review invoices raised and payments received
- Avoid manipulating dates without real business basis
Have you reviewed your tax payments on account?
You should review payments on account because overpaying creates cash strain and underpaying creates a January shock.
If your income changed significantly, you may be able to adjust payments on account, but it should be done carefully to avoid future underpayment.
Actions to take in March:
- Estimate this year’s profit realistically
- Compare to last year’s tax bill
- Decide whether adjusting payments on account is justified
Have you considered pension contributions for personal tax planning?
You should consider pension contributions because they can reduce your taxable income and improve long-term planning.
This can be particularly relevant for higher earners approaching income thresholds.
Actions to take in March:
- Check your pension contribution allowance and carry-forward
- Confirm cash flow and affordability
- Ensure payments are made before 5 April
The March checklist for landlords
Landlords can reduce tax in March by making sure property income is accurate, costs are correctly claimed, and ownership and reporting are structured sensibly before 5 April.
The biggest landlord tax mistakes are missing expenses, misclassifying repairs versus improvements, and failing to keep clear evidence of rental income.
Have you reconciled rental income to bank and agent statements?
You should reconcile rental income because HMRC focus on receipts first.
If rent is missing from records, it can create a compliance issue and a larger tax bill.
Actions to take in March:
- Pull letting agent annual statements
- Reconcile rent to bank credits
- Confirm void periods and rent holidays are documented
- Confirm deposit deductions are treated correctly
Have you captured allowable property expenses correctly?
You should review allowable property expenses because missed costs increase property profit and tax.
Typical expense headings include agent fees, repairs, insurance, safety certificates, utilities paid by you, and professional fees.
Actions to take in March:
- Gather invoices, receipts, and bank proof
- Separate repairs from capital improvements
- Confirm costs are linked to the correct property and tax year
Have you reviewed finance cost treatment and profitability?
You should review finance costs because the treatment differs depending on your structure and it affects net tax.
The goal is to understand the real after-tax profitability of each property, not just the rent received.
Actions to take in March:
- Pull mortgage statements and interest figures
- Confirm the ownership type and tax treatment
- Forecast the after-tax position
Is your ownership split still correct for your household tax plan?
You should review ownership splits because household planning can reduce tax when one partner has unused allowances or lower rates.
Ownership must reflect beneficial ownership, so you should not change splits casually or without formal support.
Actions to take in March:
- Confirm beneficial ownership position
- Compare household incomes and tax bands
- Consider whether professional advice is needed before any changes
Do you have missing records or undeclared rental income?
You should address missing records or undeclared income now because early action reduces penalty risk and stress.
If anything is missing, March is the month to deal with it before it becomes prompted by HMRC contact.
Actions to take in March:
- Identify years affected and properties involved
- Start record recovery from banks and agents
- Consider a Let Property Campaign disclosure strategy if needed
The March checklist that applies to everyone
Everyone can benefit from using allowances, tidying records, and making sure the tax year ends cleanly before 5 April.
March planning is about locking in what you can still control.
Are you using your personal allowance efficiently?
You should check whether your personal allowance is being wasted or restricted because it changes how much tax you pay on the next pound of income.
High income can reduce the personal allowance, and low extracted income can waste it, so the plan depends on your income level.
Actions to take in March:
- Estimate total taxable income for the year
- Confirm whether allowance is fully used
- Consider whether timing changes help
Are you using ISA allowances where relevant?
You should use ISA allowances if you have spare personal cash and you want tax-free growth for savings and investments.
ISA allowances reset each tax year, so March is the final window to use the current year allowance.
Actions to take in March:
- Check how much ISA allowance remains
- Confirm cash flow is stable before investing
- Avoid using business tax reserves for ISA contributions
Have you reviewed capital gains exposure?
You should review capital gains if you sold assets, disposed of property, or plan to sell before 5 April.
Timing matters because gains sit in tax years and interact with other income.
Actions to take in March:
- List disposals and estimated gains
- Check whether you have losses to offset
- Consider whether disposal timing should be before or after 5 April
Are your bookkeeping and records ready for Self Assessment?
You should tidy bookkeeping now because it reduces the risk of rushed and inaccurate tax returns later.
A clean record set also reduces the chance of HMRC questions and makes any enquiry response easier.
Actions to take in March:
- Reconcile bank accounts and bookkeeping software
- Collect missing invoices and receipts
- Create a simple folder structure by tax year
- Confirm mileage and home office evidence exists
March errors that cost people the most money
The most expensive error is doing nothing and hoping the accountant will “fix it later,” because many year-end actions are time-limited.
The second expensive error is taking a large dividend without checking tax bands, because the tax cost can be permanent.
The third expensive error is buying things just to reduce tax, because poor spending is still poor spending.
Tax planning only helps when the purchase was commercially sensible anyway.
The fourth expensive error is mixing personal and business spending with no evidence, because it creates compliance and disallowance risk.
You save tax by being organised, not by being messy.
How Total Books helps in March before the 5 April deadline
Total Books helps directors, sole traders, and landlords take the right year-end actions without guesswork.
We typically support:
- director salary and dividend planning
- pension contribution planning and timing
- Self Assessment preparation and accuracy checks
- landlord property income reviews and expense optimisation
- Let Property Campaign disclosure planning where required
- capital gains planning and timing
- bookkeeping clean-up and MTD-aligned processes
- forecasting cash reserves for future tax payments
Book a free 15-minute consultancy call and ask for a March year-end tax checklist review so you know exactly what to do before 5 April and what to leave until after 6 April.
FAQ
Can I still reduce my tax bill if I start planning in March?
Yes, March still gives you meaningful opportunities because the tax year has not ended and many allowances can still be used.
The key is acting quickly and focusing on the highest-impact areas for your income type. Directors often focus on dividends and pension contributions. Sole traders focus on allowable expenses and timing. Landlords focus on rental profit accuracy and expense capture. The best approach is to map your income position first, then choose actions that reduce tax without creating compliance risk.
What is the biggest March tax move for directors?
The biggest March tax move for directors is usually aligning profit extraction across dividends, salary, and employer pension contributions before 5 April.
A director who takes dividends without checking bands can accidentally push into higher-rate dividend tax. A director who ignores pension opportunities can miss one of the most efficient planning levers available. The right move depends on profits, cash flow, and other household income, so a short review can prevent a costly mistake.
What should a landlord check before 5 April?
A landlord should check that rental income is fully captured, expenses are correctly claimed, and finance cost treatment is understood, because these areas drive property tax outcomes.
A quick reconciliation using agent statements and bank records often reveals missing income or missed costs. Landlords should also check whether records are missing for earlier years, because early disclosure planning reduces risk. If ownership is shared, household planning may also reduce tax, but changes must reflect beneficial ownership and be handled carefully.
Should sole traders buy equipment in March to save tax?
Yes, buying essential equipment in March can reduce taxable profit when the purchase is genuinely needed and correctly treated for tax.
The key word is essential. Buying something only for tax savings is rarely good business. The safest approach is to identify purchases you were planning anyway, confirm whether they are revenue or capital, keep invoices and payment evidence, and ensure the purchase is used for business. Good recordkeeping is what makes the tax relief defendable.
What if I discover undeclared rental income or missing records in March?
You should act immediately because early action often reduces stress and penalty risk compared with waiting for HMRC to contact you first.
Start by identifying the tax years and properties affected, then begin record recovery from banks and letting agents. A structured disclosure plan, often through the Let Property Campaign approach where relevant, can help you correct historic issues and close them properly. The biggest mistake is guessing figures or sending rushed letters to HMRC without a clear calculation method.
