How can I reduce my tax bill as a small business?

Key strategies include: claiming all allowable expenses (many small businesses miss deductions), using the optimal salary/dividend split if you're a limited company director, making pension contributions (corporation tax deductible for Ltd companies), claiming capital allowances on equipment, using the Annual Investment Allowance (£1 million) for plant and machinery, working from home allowance (£6/week simplified or actual costs), claiming mileage at HMRC rates rather than actual costs if advantageous, and considering R&D tax credits if you undertake innovative work.

What expenses can I claim as a sole trader?

Sole traders can claim any expense that's wholly and exclusively for business purposes. Common claimable expenses include: office supplies and stationery, business phone and internet (business proportion), travel and mileage (45p/mile for first 10,000 miles), working from home costs, professional subscriptions, accounting fees, insurance, advertising and marketing, training directly related to your current business, stock and materials, and equipment (either as capital allowances or simplified expenses). Keep receipts for everything.

Should I use simplified expenses?

Simplified expenses offer flat-rate deductions for sole traders and partnerships that can be simpler and sometimes more generous than calculating actual costs. You can use simplified expenses for: working from home (£10–£26/month based on hours worked), vehicles (45p/mile for first 10,000, then 25p) instead of actual running costs, and living on your business premises (flat-rate deduction from income). Simplified expenses for vehicles are usually better for low-mileage, low-cost vehicles. For expensive vehicles or high mileage, calculating actual costs may give a higher deduction.

When should I switch from sole trader to limited company?

Generally, switching to a limited company becomes tax-efficient when your profits are consistently above £30,000–£50,000. At this level, the combination of paying yourself a tax-efficient salary (around the NI threshold of ~£12,570) and taking the rest as dividends becomes noticeably cheaper than paying income tax and NI as a sole trader. However, there are additional costs (accountant fees, Companies House filing, more complex admin), so the net benefit depends on your specific situation. An accountant can model both scenarios for you.

Small Business Tax Tips UK — How to Legally Reduce Your Tax Bill | PocketWise

You have a legal obligation to pay the right amount of tax — but not a penny more. Here are practical ways to keep your tax bill to a minimum.

Tax-Saving Strategies by Business Type

Sole Traders

Strategy	Detail	Potential saving
Claim all allowable expenses	Many sole traders miss legitimate deductions	Varies — could be £1,000s
Working from home	£6/week (simplified) or actual proportion of costs	£312/year (simplified) or more
Mileage allowance	45p/mile (first 10,000) then 25p/mile	Depends on mileage
Capital allowances	Deduct cost of equipment from profits	Full cost of qualifying items
Pension contributions	Tax relief at your marginal rate	Up to 45% tax relief
Use your partner	If your spouse does genuine work, pay them (uses their tax-free allowance)	Up to £12,570 tax-free
Trading allowance	First £1,000 of trading income is tax-free	£1,000
Losses	Carry forward/back losses to offset against other income	Reduces tax in profit years

Limited Company Directors

Strategy	Detail	Potential saving
Optimal salary/dividend split	Pay salary just below NI threshold (~£12,570), rest as dividends	£2,000–£10,000+/year
Employer pension contributions	Company contributes to your pension — corporation tax deductible, no NI	Up to £60,000/year
Company expenses	Claim all legitimate business expenses through the company	Varies
Capital allowances / AIA	Deduct equipment costs — Annual Investment Allowance up to £1 million	Full cost deduction
R&D tax credits	If your company does innovative work	15–27% of qualifying spend
Salary sacrifice	Sacrifice salary for pension, EV, cycle-to-work, ultra-low emission car	NI savings for you and the company
Trivial benefits	Gifts to employees/directors under £50 each (max £300/year for directors)	Up to £300 tax-free
Shareholder spouse	If your spouse is a genuine shareholder, dividends use their allowances	Up to £2,000 dividend allowance each

Allowable Expenses Checklist

Sole Traders and Partnerships

Expense	Allowable?	Notes
Office supplies, stationery	Yes
Business phone calls/contract	Yes	Business proportion only (if mixed use)
Internet	Yes	Business proportion
Postage	Yes
Advertising and marketing	Yes	Including website costs, social media ads
Accountancy fees	Yes
Legal fees (business-related)	Yes
Professional subscriptions	Yes	Must be on HMRC’s approved list or directly relevant
Insurance (business)	Yes	Public liability, PI, etc.
Business travel	Yes	Mileage, public transport, hotels for business trips
Business meals (with clients/customers)	Yes	Must be genuinely for business entertainment
Working from home	Yes	£6/week simplified or actual costs
Training (related to current business)	Yes	Must improve existing skills, NOT learn a new trade
Stock and materials	Yes
Uniforms/protective clothing	Yes	Only if specific to the job (not everyday clothes)
Equipment under £1,000	Yes	Claim in full (or use capital allowances)
Bank charges and interest	Yes	Business accounts only
Bad debts	Yes	If you’ve written off an invoice you can’t collect
Software subscriptions	Yes	Business software

Limited Companies (Additional)

Expense	Allowable?	Notes
Director salary	Yes	Corporation tax deductible
Employer pension contributions	Yes	Corporation tax deductible, no NI
Employer NI	Yes	Deductible
Staff costs	Yes
Business entertainment	No	Not allowable for CT (but no BIK if under £150/head for annual events)
Trivial benefits for directors	Yes	Under £50 each, max £300/year
Company car (electric/hybrid)	Yes	Very low BIK rates for EVs

Working From Home

Sole Traders

Method	How it works	Best for
Simplified expenses	Flat rate: 25–67 hrs/month = £10/month, 51–100 hrs = £18/month, 101+ hrs = £26/month	Simple, low costs
Actual costs	Calculate proportion of home bills used for business	Higher actual costs

Limited Company Directors

Method	How it works	Amount
Employer pays	Company pays you £6/week (£26/month) for use of home as office — no evidence needed	£312/year tax-free
Actual costs	Company reimburses actual additional costs (must be evidenced)	Varies
Rent a room	Company pays a market-rate rent for use of a room — but CGT implications on property sale	Consider carefully

Vehicle Expenses

Sole Traders — Mileage vs Actual Costs

Method	Detail	Best for
Mileage allowance	45p/mile (first 10,000) then 25p/mile	Low-mileage or low-cost vehicles
Actual costs	Claim proportion of fuel, insurance, servicing, depreciation	High-mileage or expensive vehicles

Important: Once you choose a method, you must stick with it for that vehicle.

Limited Company — Company Car vs Personal Car

Option	Tax treatment
Company car	Benefit-in-kind tax based on CO₂ emissions. Electric = 2% BIK, Petrol = 20–37%
Personal car, claim mileage	Company reimburses at HMRC advisory rates — tax-free
Personal car, claim 45p/mile	Company pays 45p/mile as employee — same as sole trader rates

Pension Contributions

Scenario	Tax benefit
Sole trader	Contributions reduce taxable income — relief at 20/40/45%
Ltd company — employer contribution	Corporation tax deductible (25% relief) AND no employee NI
Ltd company — salary sacrifice	Saves both employer NI (13.8%) and employee NI
Annual allowance	£60,000 (or 100% of earnings if lower)
Carry forward	Use unused annual allowance from the previous 3 years

Capital Allowances

Type	What it covers	Allowance
Annual Investment Allowance (AIA)	Plant and machinery	100% deduction up to £1 million/year
Full expensing (companies only)	Plant and machinery	100% for main rate items, 50% for special rate
Writing down allowance	Items not covered by AIA	18% (main pool) or 6% (special rate) per year
Small pools	Pools under £1,000	Write off in full

Common Tax Mistakes

Mistake	Cost
Not claiming all allowable expenses	Overpaying tax
Not keeping receipts	Can’t substantiate claims if HMRC enquires
Missing the Self Assessment deadline	£100 fine + interest
Not registering for VAT when required	Penalties and back-dated VAT owed
Taking too high a salary from a Ltd company	Unnecessary NI charges
Not paying into a pension	Missing significant tax relief
Not claiming mileage	Free money left on the table
Mixing personal and business finances	Record-keeping nightmare, risk of incorrect claims

Small Business Tax Tips UK — How to Legally Reduce Your Tax Bill

Contents

Tax-Saving Strategies by Business Type

Sole Traders

Limited Company Directors

Allowable Expenses Checklist

Sole Traders and Partnerships

Limited Companies (Additional)

Working From Home

Sole Traders

Limited Company Directors

Vehicle Expenses

Sole Traders — Mileage vs Actual Costs

Limited Company — Company Car vs Personal Car

Pension Contributions

Capital Allowances

Common Tax Mistakes

Useful Links

Sources