Netflix is clamping down on customers freely sharing passwords with people they don’t live with.

More than six months after first revealing plans to tackle viewers still splitting accounts, the streaming service has started sending the first emails warning holders they must stop.

With a cost of living crisis reportedly impacting on subscribers, Netflix first suggested in October last year intentions to deal with the ‘millions’ of people it suspected were piggy-backing off other people’s accounts.

While sharing passwords has always been prohibited by Netflix the company has never introduced a system to enforce the rules globally.

But with an estimated 100 million households, it suggests, sharing accounts to save cash, the company says the issue is undermining its 'long term ability to invest in and improve Netflix as well as build our business'.

In a statement posted online Tuesday, Netflix said: “Starting today, we will be sending this email to members who are sharing Netflix outside their household in the United Kingdom.

“A Netflix account is for use by one household.

“Everyone living in that household can use Netflix wherever they are – at home, on the go, on holiday – and take advantage of new features like Transfer Profile and Manage Access and Devices.

“We recognise that our members have many entertainment choices. It’s why we continue to invest heavily in a wide variety of new films and TV programmes – so whatever your taste, mood or language and whoever you’re watching with, there’s always something satisfying to watch on Netflix.”

The new rules

Warnings to customers Netflix believes could be sharing passwords will start to trickle out in the UK this week.

The message, also outlines the new rules, should people be determined to continue sharing profiles with people they don’t also share a home with.

Options include transferring that current profile to the person living outside the home, along with entering new payment information that they can take responsibility for.

Alternatively – there is also now the option ‘to buy an extra member’ which will cost £4.99 a month and can enable an account holder to share with someone not in their household.

Exactly how Netflix intends to enforce the new payment structure and detect viewers breaching the guidance is unclear.

However current information on its website says the company can use details such as IP addresses, device IDs, and account activity from devices signed into an individual Netflix account to spot those in breach, alongside adopting device verification to confirm exactly who is logging in.

It is also expected that anyone attempting to log-in with a shared password will begin to see a warning pop-up prompting them to take out one of the new options designed to stop password sharing.

At the end of last year Netflix also announced a cheaper ad-based subscription service to lure avid film and television fans in with a cut-price deal.

Households in the UK can pay just £4.99 a month for an account to watch Netflix television shows and films interspersed with adverts - but they are only be available to stream on one device at a time.