Barcelona airport
Barcelona airport is the second busiest airport in Spain with nearly 53 million passengers. Pau Barrena/AFP News

Travellers heading to Spain have been issued a warning about a possible £513 fine over breaching a taxi rule.

People must do thorough research before visiting Spain as the western European country has been coming up with several rules for both locals and foreigners to maintain order across cities. Breaking simple rules could lead to hefty fines, thereby ruining one's holiday.

The majority of holidaymakers typically book an airport transfer to get to their accommodation, while others may decide to flag down a cab once they land. However, they must know that Spain has very strict rules about airport transfers.

Taxi scam in Spain

Travellers should be aware that in Spain, taxis must be registered and the laws around taxis and private hire companies are very severe. Not only can unregistered drivers get into trouble, but passengers using these services can also be slapped with a hefty fine.

There are quite a few illegal transport companies, especially in popular tourist hotspots that pretend to have registered and legit businesses. They attract tourists by offering cheap prices. So, one must be careful when booking a transfer or getting in a taxi while on holiday, as a person could be fined up to €600 (£513 ) if caught using an unlicensed service.

UK Foreign Office's advisory

The UK Foreign Office has also warned its people about this rule. "Only use official registered or licensed taxis, or reputable transport companies you recognise. Licensing regulations differ across Spain and in certain cities pre-booking is required. Passengers caught using unlicensed taxi services are liable for fines of up to €600. Make sure you book your taxi or airport transfer through a licensed firm," the Foreign Office writes in its advisory.

If a traveller isn't sure about a car company, they can always ask the driver to show their legal papers and registration to be 100% sure before making a reservation with them.

Meanwhile, there are a few ways to find out if the cab firm is legitimate. If a transfer company asks to meet the traveller anywhere apart from the designated area outside the arrivals terminal, they could likely be unregistered. Their vehicles will also not be insured for passenger liability cover.

It has also been reported that at big airports such as Madrid and Malaga, there are a lot of regular checks to stop unlicensed taxi firms from operating. The car parks are frequently checked by police and inspectors who are looking for illegal drivers.

Another strict rule in Spain

The taxi rule is not the only one that could see British travellers lose money. Since the UK is not a part of the European Union (EU) anymore, people who do not hold an EU passport now have to show proof of their accommodation. Holidaymakers have to carry these documents when on holiday as tourists for 90 days or less in Spain.

It is never a problem to receive proof of their stay if a traveller makes a reservation in a hotel or hostel. However, it may get tricky if they stay at a relative or friend's house. In this case, a traveller in Spain needs a "letter of invitation" or "carta de invitacion" from their relative or friend who will be hosting them in the country.

If a person visits Spain without proof of accommodation, they will have to pay a fine. And if they do not have the letter of invitation, their hosts could be slapped with a fine of £8,000.

The invitation letter isn't just a note from the host but an official statement that has to be issued by the local police. The person who will be hosting you in Spain needs to be either a Spanish national, an EU citizen living in Spain or a non-EU citizen with legal residence.