Holidaymakers face being locked out of winter ski destinations because the NHS app does not record booster vaccinations.
Travel chiefs warned that the omission could lead to holidaymakers seeking winter snow being denied access to countries which now require three jabs unless the NHS updated its app to include the boosters.
Austria and Switzerland are among a growing number of nations setting time limits on the validity of vaccinations unless travellers have boosted their immunity with follow-up jabs.
Croatia and Israel have imposed similar limits, effectively timing out travellers unless they have had their boosters.
Lithuania, the first country to roll out a digital Covid pass, has also now become the first EU country to include boosters in its app for its citizens, setting a precedent for other nations.
The Department of Health and Social Care admitted it had not designed the UK app to include boosters as “they are not required for domestic certification”.
It also noted that most countries did not currently require boosters as an entry requirement, although it was “aware” that some countries had begun introducing expiry dates on vaccination for travel.
“We know some countries are altering their vaccine requirements, so we continue to keep international travel certification under review to ensure British citizens can travel abroad as easily as possible,” said a spokesman.
Paul Charles, the chief executive of travel consultancy The PC Agency, said: “The Government urgently needs to update the app so it recognises those who are getting their boosters.
“It is vital systems are as up to date as possible, otherwise other countries will stop letting people in. We have to see the app updated in real time as soon as you have had your booster otherwise it puts at risk your next trip.”
Karen Dee, the chief executive of the Airport Operators’ Association, said the NHS app needed to “evolve” in line with changing travel rules.
“The NHS Covid Pass must evolve too to enable people to prove they have had their booster vaccine where required. Other countries’ digital apps already include boosters, and we will work with the four UK governments to ensure the UK apps do so too,” she said.
Austria will treat jabbed travellers as unvaccinated unless they have had a booster within 360 days, or just under 12 months, of their second dose. This means they will be required to pay for a Covid test to secure entry.
Swiss health authorities consider that a person is fully vaccinated only “for a period of 12 months from the date of complete vaccination.”
The lack of a Covid pass without a booster jab could also pose problems on the slopes and for entry to restaurants, clubs and leisure facilities.
Austrian and Italian resorts demand full vaccination
Austria has joined Italy in requiring all skiers in ski resorts this winter to be fully vaccinated, show proof of recovery or a negative Covid test to access enclosed ski lifts as well as bars and restaurants around a resort.
Everyone over 16 in Switzerland must now hold a Covid certificate – proof of Covid vaccination, recovery or a negative PCR/antigen test every three days – at hospitality venues including bars and restaurants, large-scale events and indoor sporting activities.
Israel has the toughest rules, allowing visits only if they are due to end no more than 180 days after the second dose. Travellers can enter the country if they have “received a booster dose and at least 14 days have passed by the day of entry into Israel,” the rules state.
As a result, many double-jabbed British travellers face being excluded – although people who have proof of recovery from Covid within the previous 190 days, or six months, will be allowed in. Croatia has put a 270-day limit on vaccine validity.