Lovelorn Britons lost £41 million to online romance fraudsters in 2017, new research has revealed.
A study by a new task force set up to tackle the issue found that each victim lost an average of £11,500 to their supposed love interest.
The most common modus operandi was for fraudsters to create a fake online profile on dating sites and enter into a "relationship" with the victim.
Having gained their trust, the fraudsters then ask for cash or coax the victim to hand over personal information.
A total of 3,557 romance frauds were reported in 2017, with women more likely than men to fall prey to the scam - making up 63% of the victims.
Police believe the true figure could be much higher as many romance frauds may go unreported due to embarrassment on the part of the victim - 43% said it had a "significant" impact on their health or wellbeing.
A further 18% were at risk of bankruptcy or had received medical treatment as a result of romance fraud.
Older people were more vulnerable, with 25% of victims in their 50s, 22% in their 40s and only 13% under 30.
The statistics were compiled by #DateSafe, a working group comprising of charities Get Safe Online, Age UK, Victim Support, as well as City of London Police, the Met and the Online Dating Association.
They advise those on an online quest for love this Valentine's Day not to rush into a relationship as well as running their prospective date's name and any profile pics through a search engine with the words "dating scam".
#DateSafe is also warning never to send money to or share bank details with someone you've met online, regardless of the reason they give or how long you have been talking to them.
Other tips include talking to your friends and family about your dates, meet in a public place and be wary of anyone who tells you not to tell others about them.
Tony Neate, chief executive of Get Safe Online, said: "Lots of happy relationships are built as a result of meeting someone online.
"However, as in any form of dating, there are some nasty characters out there who will try and take advantage of someone looking for love."
The City of London Police's Commander Dave Clark, the national coordinator for economic crime, said: "Fraud can manifest itself in many different forms and is constantly evolving; it can have a major impact on victims, both financially and psychologically.
"In the case of dating fraud, the emotional damage is often far more difficult to come to terms with.
"These callous criminals will target vulnerable victims for their own monetary gain and our latest intelligence tells us that women in their forties are the most likely to be tricked in this way.
"We are therefore urging people to spot the signs of dating fraud in order to protect themselves and to follow the 'Date Safe' advice this Valentine's Day and in the future."
He urged those who believed they may have fallen victim to a romance fraud to contact police.