The rules, written down so nobody has to guess.
How a slot is matched to your window, what counts as being in the queue, and what you see when something goes wrong. Identical for the passport / national ID service and the migration service.
01
Matching a slot to your window
The start of a time range is included, the end is not. Dates are included at both ends.
- 08:45not bookable
- 09:00bookable
- 10:30bookable
- 11:45bookable
- 12:00not bookable
| Rule | Result |
|---|---|
| Start of a time range | Included:09:00 is bookable |
| End of a time range | Excluded:12:00 is not bookable, 11:45 is |
| First and last day of the date range | Included:Both count: 21 Oct and 31 Oct are in |
| Only a start date | That date onwards, with no end |
| Only an end date | From now until that date |
| Start and end are the same day | That single day only |
| Morning, Afternoon or Anytime | Morning is before 12:00, Afternoon is 12:00 onwards, Anytime is the whole day |
| Several date ranges | A slot is bookable if it matches any date range, using that range's own time of day |
| As soon as possible | Ignores the dates and takes the very first slot that appears |
| Which clock | The embassy's local time (London) on both systems, whatever the server's timezone |
| How far it looks | 12 weeks for passports and ID cards, 8 for migration, and it says when it stops |
02
What counts as “in the queue”
One number per exact slot, per service. A passport slot and a migration slot never mix, even at the same minute.
Pending
Someone confirmed a booking request and it is running.
Counts
Booked
The appointment is confirmed. It still holds the slot.
Counts
Stale
No progress for 15 minutes, so the slot is released.
Does not count
Released
Failed, cancelled or timed out. The entry is deleted.
Does not count
Counted
- Other people pending on that exact slot
- People already booked on that exact slot
- Entries refreshed within the last 15 minutes
Not counted
- Failed, cancelled or timed-out attempts
- The website's own “3 free” label, shown separately and never merged
- Your own attempt is labelled as yours, never hidden in the crowd
- People queued for a different slot, even on the same day
03
When things go wrong
Every one of these behaves identically in the passport flow and the migration flow.
- No free slot inside the window
- A clear message plus the nearest slots outside the window, so it can be widened. Nothing is booked.
- Free slots exist, but all outside the window
- They are listed once, marked “outside your window”, and never booked.
- The window itself is invalid
- The bot refuses it with a message naming the broken range, and keeps the last valid window. Never a silent fallback to booking anything.
- The website changes its layout
- The booking stops, the browser stays on the right page, and you are told to finish it by hand. Never a half-finished booking.
- The slot is gone by the time it is clicked
- The queue entry is released, the count goes back down, and the bot keeps looking.
- The booking succeeds
- You get the confirmation and booking number, and the slot's count stays one higher because the slot is taken.
See the rules at work on live slots.
Open the console