Electrician on £70,000

Sole Trader. Age 44. Pension preference: modest.

Every figure on this page is computed at build time by the same engines that power the live salary–dividend split, take-home and SIPP optimiser calculators. Inputs come from a single CSV row; outputs come from the engines. No static lookup tables, no hand-coded numbers.

Net cash

£49,702

Pension

£0

Effective rate

24%

Marginal rate

42%

Step by step: how the engine arrived at the bottom line

For a sole-trader electrician with £70,000 of turnover, the engine evaluated each stage of the Self Assessment chain in HMRC's order:

Turnover: £70,000.
Expense vs trading-allowance decision: the £1,000 trading allowance (ITTOIA 2005 s.783A) lost to actual expenses and was discarded.
Taxable profits: £66,500.
Income tax: £14,032 (rUK bands, after Personal Allowance).
Class 4 NI: £2,587 (6% £12,570–£50,270, 2% above).
Class 2 (voluntary): £179 — £179.40/yr, paid to maintain a State Pension qualifying year per HMRC's voluntary NI guidance.
Net cash: £49,702. Effective rate on turnover: 24%.

The numbers, line by line

Turnover	£70,000
Taxable profits	£66,500
Trading allowance vs actual expenses	Actual expenses
Income tax	£14,032
Class 4 NI	£2,587
Class 2 NI (voluntary)	£179
Net cash (year)	£49,702
Net cash (monthly)	£4,142
Hours-equivalent at NLW (£12.21/hr)	4,071 hrs
Effective rate	24%
Same turnover as Ltd Co (no pension)	£50,231
Incorporate vs stay sole trader	+£529 for Ltd Co

Why this scenario is different

Compared to the closest peer profile — Freelance developer at £70,000 — this scenario sits £0 higher on gross income. That moves net cash by +£0, the pension contribution by +£0, and the effective rate by +0%. The effective rate moves only modestly — both scenarios sit inside the same binding tax band. Taxable profits change from £66,500 to £66,500 (after the trading-allowance / actual-expenses choice).

Questions this scenario raises

Are the engine assumptions documented anywhere?

Yes — every constant lives in src/lib/tax/constants.ts with a source-URL comment. Every engine function is unit-tested against HMRC examples (180+ test cases). The full methodology is at /about and the per-engine assumptions are spelled out at the foot of each calculator.

Are the numbers on this page computed live or pre-rendered?

They are pre-rendered at build time by running the BracketMath engine code against the inputs for this specific row. That means: zero JavaScript on the page for the calculation itself, the figures cannot drift if the engine is changed, and you can verify them by running the corresponding calculator with the same inputs.

What does the "marginal rate" mean on this page?

It is the rate paid on the next £1 of gross income added to this scenario. For this row that figure is 42.0%. The marginal rate is always higher than the average effective rate — it is the right number for "is one more invoice worth it" decisions.

What is the £1,000 trading allowance and when does it help?

The trading allowance (ITTOIA 2005 s.783A) lets a sole trader deduct a flat £1,000 from gross trading income in lieu of claiming actual expenses. It strictly beats actual expenses whenever expenses are less than £1,000. The engine picks whichever produces lower taxable profits — for this row the chosen route is shown in the comparison table.

Should I incorporate this sole-trader business into a Ltd Co?

At this turnover, the pure-tax saving from incorporating is only £529/year — almost certainly less than the ~£800–£1,500/yr accountancy and admin overhead of running a Ltd Co. Stay a sole trader unless turnover scales materially.

Methodology

Income tax, National Insurance and Corporation Tax bands taken from HMRC's 2026/27 rates and allowances tables (gov.uk/.../income-tax; corporation-tax). Pension Annual Allowance and taper rules from Finance Act 2004 / 2023. Trading allowance per ITTOIA 2005 s.783A. Voluntary Class 2 figure (£179.40/yr = £3.45/wk × 52) from HMRC voluntary NI guidance.

Style: 2026/27 tax year throughout; figures rounded to whole pounds in the user-facing prose; effective rates computed as (deductions / gross). The voice is methodological — no first person, no claimed credentials, no marketing fluff.

This page is not personalised advice; for advice regulated by the FCA, consult an adviser registered with the Financial Conduct Authority. See the full disclaimer.