One question first.
Then we open your file.
No email. No card. Answer as much or as little as you like — what you tell us is written into your file as you go, and travels with you into whichever door you choose.
Tell us your details once, and the same answers can move through the steps that follow.
With the details to hand, the report that notifies the public-sector bodies can take around twenty minutes rather than 60–90 — the saving is having things gathered, not the service itself.
Once a National Insurance number is recorded, the form itself can take about five minutes rather than 15–20. The rest is usually the hunt for the number.
A single Tell Us Once report can reach HMRC, DWP, DVLA, the Passport Office and your local council at the same time — public-sector bodies only; banks and insurers are told separately.