GOV.UK: cognitive load example to copy

What to steal

Name the one thing the person needs before the button. Here it is the registration number.
Make the primary action a large button and keep the other links smaller.

What to test next: This page vs the same task with the registration number explained only after Start now. Measure checks completed and time to the first result.

In plain words

Why it works

GOV.UK uses cognitive load: detail that does not help the task uses up the effort people have for it (Sweller 1988). This page asks for one fact. “Find out if a vehicle has an MOT certificate and when it runs out. You’ll need the vehicle’s registration number (number plate).” Under that is a green “Start now” button, with “on the vehicle enquiry service” beneath it. The button is the large, close target Fitts’s law is about: the time to hit a target depends on its size and distance (Fitts 1954). Other links, such as “Check the MOT history of a vehicle”, stay in a smaller list on the right. Whether the short page makes more people finish the check is not public.

Honest nudge or dark pattern?

Honest nudge

Honest nudge: the only requirement is named before you start, the button says “Start now”, and the Welsh version is linked on the same screen.

Sources: Captured by Nudgeswipe, 4 Nov 2026 (UK service page, logged out)

Context

GOV.UK, “Check the MOT status of a vehicle”, logged out, on 4 Nov 2026. Additional cookies were rejected and the cookie message was hidden. The page also links “in Welsh (Cymraeg)”.

The research

The research behind it

● Strong evidence · More on cognitive load, with sources →

Next: run it on your product

Try it on your own product

Opens your assistant with this teardown, our verdict and the steps above. It asks about your product first, then suggests tests you can run.

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You are helping me apply a behavioural-design pattern ethically.

Pattern: GOV.UK: GOV.UK asks for a number plate, then a large Start now
Bias: Cognitive load: Mental effort spent on processing a task leaves less capacity for learning or judging it.
Why it nudges: GOV.UK uses cognitive load: detail that does not help the task uses up the effort people have for it (Sweller 1988). This page asks for one fact. “Find out if a vehicle has an MOT certificate and when it runs out. You’ll need the vehicle’s registration number (number plate).” Under that is a green “Start now” button, with “on the vehicle enquiry service” beneath it. The button is the large, close target Fitts’s law is about: the time to hit a target depends on its size and distance (Fitts 1954). Other links, such as “Check the MOT history of a vehicle”, stay in a smaller list on the right. Whether the short page makes more people finish the check is not public.
Our verdict: Honest nudge. Honest nudge: the only requirement is named before you start, the button says “Start now”, and the Welsh version is linked on the same screen.
Source page: https://nudgeswipe.com/examples/gov-uk-mot-one-fact-then-start/ (JSON: https://nudgeswipe.com/api/teardowns/gov-uk-mot-one-fact-then-start.json)

Rules: say a brand "uses" a tactic, never that it "worked"; outcomes are not public unless the company published them; no invented uplift estimates; flag mixed evidence. Honest nudge = true, visible, easy to reverse, and in the user's interest. Dark pattern = hides costs, fakes scarcity or popularity, shames, or makes leaving harder than joining. Quote company-published results as "X reports", with the source link, and don’t generalise them. Don’t cite retracted or failed-to-replicate studies as support (e.g. Ariely & Wertenbroch 2002). Don’t state study figures unless they’re on this page or in a source you can link. If an idea crosses the line, link the matching deceptive.design pattern.

Tasks:
1. Ask me for my product, the flow (URL or screenshots) and the goal.
2. Audit where this pattern already appears, or could, in that flow.
3. Propose 2-3 ethical experiments: hypothesis, variant copy or UI, primary metric, and a guardrail metric (refunds, complaints, cancellations).
4. Flag every dark-pattern risk and say how to stay on the honest side.

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Sources

Our capture of gov.uk, 4 Nov 2026
Sweller (1988), Cognitive Load During Problem Solving: Effects on Learning. doi.org/10.1207/s15516709cog1202_4
Captured by Nudgeswipe, 4 Nov 2026 (UK service page, logged out): gov.uk

GOV.UK asks for a number plate, then a large Start now

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Why it works

Honest nudge

The research behind it

Try it on your own product

5 new nudges, every Friday