Many users ask is Kodi illegal and officials have warned that the use set-top boxes "is not a petty crime".
A report released has suggested Kodi boxes are being used by hundreds of thousands of British households to access paid-for content illegally.
Kodi is a method of adding on premium content such as live football streams and movies. It can also be used with other devices such as Amazon Fire Sticks.
"Consumers need to be aware that streaming paid content for free is absolutely illegal"
Is Kodi illegal?
Kodi is legal but many of the add-ons that users in the UK access, are not.
Many users of Kodi do not realise they are breaking the law, largely because the rules have been vague in the past.
According to a report by the Intellectual Property Office (IPO) and the Federation Against Copyright Theft (FACT), more than one million Kodi boxes have been sold in the UK over the past two years.
Kieron Sharp, director general at FACT, said: "A quarter of Brits access digital material illegally, and often don’t realise the risks associated with that, for them and their families.
"Pirates are not Robin Hood characters; they are criminals who do it to make money through illicit means.
"As a result, the risks are high – inappropriate advertising that could be seen by young children, electrical safety associated with counterfeit parts, and financial cyber crime.”
'Not a petty crime'
Detective Chief Inspector Pete Radcliffe, head of the Police Intellectual Property Crime Unit said: “While it may be tempting for people to think they are getting a bargain when streaming illegally, it’s important to remember that there are organised criminals behind it, often associated with other serious crimes.
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"Pirating content is not a petty crime; from release groups, to site operators to set-top box wholesalers and distributers, there is an international criminal business model.”
Crime and Punishment
The report outlines the level of punishment for people caught breaking online copyright laws.
It says: "The new Digital Economy Act which comes into effect on 1 October 2017, has extended criminal penalties for online copyright infringement to match those of physical copyright infringement – maximum sentences will increase from two years to 10 years.
"This could mean longer custodial sentences for the criminals involved in distributing ISDs.
“We have seen an increasing number of unofficial apps and add-ons emerging that allow illegal access to copyrighted content such as live sport, films and premium pay-to view
TV via mobile phones, tablets and TV set-top boxes.
"Consumers need to be aware that streaming paid content for free is absolutely illegal.
"While our priority remains to crackdown on the individuals behind this criminality, end users may find themselves getting swept up in one of our operations and becoming part of the whole criminal investigation.”