Is 40 too old to become a train driver?

No. Forty is a normal age to apply. Fifty-five is not a hidden cutoff either. Operators write a minimum age on the vacancy, often 18 or 21. They do not write “must be under 40”.

The real filters are whether you meet that advert, whether you pass the medical, and whether you can still be accurate on a long, dull, timed day. The tests do not know your birthday.

What the advert actually says

There is no one national age rule. Each operator sets eligibility on that vacancy: right to work, sometimes GCSEs or a licence, and a minimum age. Read it. Forum lists go stale the moment an intake changes.

Starting at 40 or 55 still leaves years of driving after training. Training itself is commonly the better part of a year. You cannot speed up that calendar. You can avoid spending a scarce assessment attempt on a format you have never seen.

The medical, not the candles

There is a medical. Eyesight, hearing, and general fitness are part of it. That bar exists for safety, not to keep people in their thirties out. If you have a condition you are unsure about, ask occupational health or your GP, not a thread that ends with “I heard they fail anyone over 50”.

Shift work is the other honest check. Nights, earlies, and a roster that does not care it is your child's assembly. Age does not disqualify you. Pretending you want that life when you do not will.

What still catches people at 40 and 55

The same things that catch a 25-year-old: walking in cold, skipping vigilance, rushing Group Bourdon, guessing on judgement. Career-changers often have the composure. They still fail the wrapper if they have never sat it.

Practise the timed battery. Read the vacancy. Then apply. Forty is not too old. Fifty-five is a medical and a roster question, not a secret no.