All new web addresses registered in the UK will be screened for terms that signal or encourage serious sexual offences.
Nominet, the organisation that oversees all the UK's web addresses, said all domain names will be checked within 48 hours of registration.
If an address is found to contain a prohibited term it will be suspended or de-registered.
Existing web addresses will also come under the new rules.
Nominet took this course of action after the publication of a policy review by former director of public prosecutions Lord Macdonald.
In his report he recommended that the company implemented post-registration screening specifically for domain names that "signal sex-crime content".
Nominet has not published the list of prohibited terms.
However, Lord Macdonald said Nominet should limit their screening to sex-crime terms only, as there was a better chance of these being identified than other, more general, forms of criminality.
He also said the firm should have "no role in policing questions of taste or offensiveness on the internet".
Eleanor Bradley, chief operating officer at Nominet told the BBC that the registration service was not trying to censor the internet.
Legitimate names protected
"This is not about domain names that offend, or about swear words, it is about criminal acts relating to sexual offences," she said.
Once a domain name is registered it will be examined by a computer algorithm looking for terms relating to sex crimes.
Any address that is flagged as containing one of the prohibited words or phrases will then be checked by a human. This is to ensure that legitimate domain names are not suspended unnecessarily.
An example of a legitimate website, that might be flagged by the algorithm, is one set up to help victims of rape. Or where a flagged word is contained within another word.
Any domain name containing a sex crime term that does not appear to have a legitimate use would be reported to the police.
Nominet's register of web addresses has over 10.5 million entries. It said it expects only a handful of the 150,000-200,000 new registrations each month to be flagged under the new process.
The company will explain how it intends to implement the new policy in early March and will also update its terms and conditions to specifically cover these changes to the registration process.