New rules designed to clamp down on the funds used to finance organised crime and terrorism will be rolled out on Monday.
The move will force businesses to carry out more rigorous checks on the money flowing through the UK financial system in a bid to stop terrorists in their tracks.
The Government said the rules will affect banks, accountants, estate agents and casinos and are designed to help firms check the money they receive is coming from an honest source.
Economic Secretary to the Treasury Stephen Barclay said the Government was "cracking down on terrorists and criminals funnelling money through our financial system".
He said: "Terrorist financing and money laundering are a significant threat to our national security, and we are determined to make the UK a hostile environment for illicit finance.
"These new rules will tighten our defences, protect the integrity of our financial system and help protect the British public from terror attacks and criminal activities."
The rules will help police stop a potential terrorist attack by giving companies the power to spot suspicious activity and report it to the authorities quickly.
The Government said it needs a "strong toolkit" to counter serious and organised crime, which costs Britain around £24 billion each year.
It added: "Although the vast majority of businesses are vigilant, these new rules will ensure that they are not abused by criminals or terrorists looking to move funds or obscure assets."
Britain's biggest banks gave authorities 24-hour support during the recent spate of UK terror attacks in order to provide financial intelligence to the police.
The regulations put into force the EU 4th money laundering directive.