Self-Employment Guides UK — Tax, Business Setup, and Running Your Own Business

Contractor Day Rate to Salary — UK Conversion Calculator & Guide

Convert contractor day rates to equivalent salary and vice versa. Worked examples for inside and outside IR35 contractors, with take-home pay comparisons for 2026/27.

Self-employment tax and business information is based on current HMRC rules. This is not tax or accounting advice. Consider consulting a qualified accountant for your specific circumstances.

Whether you’re moving from permanent employment to contracting or comparing contract offers with permanent roles, understanding the day rate to salary conversion is essential. The headline number rarely tells the full story.

Basic Day Rate to Salary Formula

The simplest conversion:

Annual equivalent = Day rate × Working days per year

The key variable is working days. Here’s what most contractors use:

Scenario Working Days Basis
Maximum (optimistic) 252 365 minus weekends and 8 bank holidays
Realistic (industry standard) 220 Allows for 25 days holiday + 7 sick/admin days
Conservative 200 Allows for gaps between contracts
First-year estimate 180-200 Ramp-up time, finding first contract

Using 220 days:

Day Rate Annual Equivalent
£250 £55,000
£300 £66,000
£350 £77,000
£400 £88,000
£450 £99,000
£500 £110,000
£550 £121,000
£600 £132,000
£650 £143,000
£750 £165,000

Salary to Day Rate Conversion

Going the other direction, divide your target salary by working days:

Day rate = Target annual income ÷ 220

But this doesn’t account for employer costs that permanent employees receive for free. A fair comparison needs adjustments.

The True Cost of Employment Comparison

A permanent employee on £60,000 actually costs their employer roughly:

Component Value
Base salary £60,000
Employer NI (13.8% above £9,100) £7,024
Employer pension (5-8%) £3,000–£4,800
Holiday pay (25 days + 8 bank holidays) Included in salary
Sick pay, maternity/paternity Included
Training budget £500–£2,000
Equipment, office space Variable
Total employer cost ~£72,000–£75,000

To truly match a £60,000 permanent salary, your day rate needs to cover the equivalent of £72,000–£75,000 in total employment value.

Equivalent day rate: £72,000 ÷ 220 = approximately £327/day

Inside vs Outside IR35 — Take-Home Comparison

Your IR35 status dramatically affects how much you keep from each day rate.

£400/Day Outside IR35 (Ltd Company)

Operating through your own limited company with a tax-efficient salary/dividend split:

Item Amount
Gross annual income (220 days) £88,000
Allowable expenses (accountant, insurance, travel) -£5,000
Company profit £83,000
Director salary (optimal level) £12,570
Corporation tax (25% on £70,430) -£17,608
Retained profit for dividends £52,822
Dividend tax (8.75% on first £37,700; 33.75% above) -£8,393
Employee NI on salary £0 (below threshold)
Approximate take-home £56,999
Effective tax rate ~35%

£400/Day Inside IR35 (Umbrella Company)

Through an umbrella company, you’re taxed like an employee:

Item Amount
Gross annual income (220 days) £88,000
Umbrella margin -£600
Employer NI (deducted from your pay) -£10,888
Apprenticeship levy (0.5%) -£440
Gross taxable pay £76,072
Income Tax (20% + 40%) -£17,498
Employee NI (8% + 2%) -£4,862
Approximate take-home £53,712
Effective tax rate ~39%

Difference: ~£3,300/year more outside IR35 at this day rate, with the gap widening at higher rates.

£600/Day Comparison

Outside IR35 Inside IR35
Gross (220 days) £132,000 £132,000
Approximate take-home £82,000 £74,500
Effective tax rate ~38% ~44%
Difference +£7,500

Adjustments Contractors Must Budget For

Your day rate must cover costs that permanent employees get for free:

Non-Working Days

  • 25 days holiday — no pay for holidays (already factored in 220-day calculation)
  • Sick days — no statutory sick pay as a Ltd company director
  • Gaps between contracts — average 2–6 weeks per year

Business Costs

Cost Annual Estimate
Accountant £1,200–£2,000
Professional indemnity insurance £200–£600
Public liability insurance £100–£300
IR35 contract review £200–£400 per contract
Business bank account £60–£180
Software & tools £200–£500
Pension contributions (self-funded) 5–15% of income

Pension Gap

Permanent employees typically receive 3–8% employer pension contributions on top of salary. As a contractor, this comes from your day rate. Budget at least 10% of gross income for pension to match permanent pension benefits.

Quick Reference — Day Rate Equivalents

This table shows the permanent salary you’d need to match each day rate’s take-home (outside IR35, after all costs):

Day Rate Gross (220 days) Take-Home (Outside IR35) Equivalent Perm Salary
£250 £55,000 ~£38,000 ~£42,000
£300 £66,000 ~£44,500 ~£50,000
£350 £77,000 ~£51,000 ~£57,000
£400 £88,000 ~£57,000 ~£63,000
£450 £99,000 ~£63,000 ~£70,000
£500 £110,000 ~£69,000 ~£78,000
£600 £132,000 ~£82,000 ~£96,000
£750 £165,000 ~£99,000 ~£120,000

Factors That Affect Your Actual Day Rate

Industry and Demand

Day rates vary enormously by sector:

Sector Typical Range
IT/Tech £350–£750
Finance/Banking £400–£800
Engineering £300–£600
Management consulting £500–£1,200
Project management £350–£600
Healthcare (locum) £300–£700

Location

London rates are typically 15–25% higher than regional rates. Remote work has narrowed this gap since 2020, but London-based contracts still command a premium.

Contract Length

  • Short contracts (1–3 months) — command higher rates but more gaps
  • Long contracts (6–12 months) — slightly lower rates but more stability and fewer gaps
  • Rolling contracts — best of both worlds but with IR35 scrutiny

Making the Decision — Contract vs Permanent

Before jumping to contracting, ensure your day rate covers:

  1. Equivalent salary — match or beat your permanent take-home
  2. Lost benefits — pension, holiday pay, sick pay, life insurance, private medical
  3. Business costs — accountant, insurance, admin time
  4. Risk premium — contract termination at short notice, gaps between contracts
  5. Career development — no employer-funded training or progression

A common rule of thumb: your day rate should be at least 40-50% higher than the permanent salary daily equivalent to make contracting worthwhile after costs and risk.

For a £60,000 permanent role: £60,000 ÷ 220 = £273/day. Add 50%: minimum £410/day to consider contracting.

Sources

  1. HMRC — Off-payroll working (IR35)