Nearly one million drivers in the UK could be facing a £1,000 fine after failing to meet an important deadline on their driving licence, according to new data.
Driver and Vehicle Licensing Agency (DVLA) figures showed 926,000 people were holding a photo ID driving licence card that expired in the 12 months to the end of August.
The number, obtained by the PA news agency following a Freedom of Information request, represents two per cent of all drivers.
While driving entitlement is normally valid until someone reaches the age of 70 - after which they must renew their licence every three years to stay on the road - p hotocards must be renewed every 10 years to ensure the image remains a true likeness of the driver.
Expiry dates are displayed in section 4b on the front of cards.
Not returning an expired licence to the DVLA is an offence under the Road Traffic Act 1988, and can result in a hefty fine of up to £1,000.
The DVLA writes to people 56 days before their licence ends to remind them to renew, but many drivers miss the letters as they do not inform them when their address changes.
A fine is not issued for renewing late, and a person can usually continue to drive while the DVLA handles their renewal, provided they follow the rules of their previous licence.
Philip Gomm of the RAC Foundation said: "There are good reasons to keep licences up to date, beyond the basic legal requirement.
"They are also a widely accepted form of ID and will certainly be required if you are ever stopped by police.
"Renewal also provides an opportunity for people to assess whether they are still fit to drive, and we think there is an argument for linking a compulsory eye test to the process to make sure we all remain safe on the road, though Government should help keep costs as low as possible for motorists."
A total of 2.5million people renewed their photo ID licence in the year to the end of August, with a small proportion of the 926,000 who missed the deadline thought to have stopped driving without notifying the DVLA.
The DVLA advised people to renew on its official website, as it is the quickest and cheapest method. Applications cost £14 and are usually processed within five days.
Postal renewals cost £17, while doing it at a Post Office has a £21.50 fee. Motorists should avoid third-party websites, however, which can charge additional fees.
A DVLA spokeswoman said: "We encourage customers to use GOV.UK as applying online is the quickest and cheapest way to renew their photocard driving licence.
"If you stop driving altogether, you should inform DVLA and return your licence rather than keeping it as a form of out-of-date photo ID."