For the first time, UK internet access is being included in the telephone services that all customers should get as standard.
Complain if your line speed is slow
The new guidelines also demand that BT and Kingston Communications give all customers this net access at a minimum speed.
Users who are not able to access the net via a dial-up account at this speed will be able to demand that their telephone provider do something about it.
The new minimum standards come into force on 25 July.
Only two of the UK's fixed line phones firms, BT and Hull's Kingston Communications, have an obligation to meet the universal minimum standards defined by Oftel.
These standards require the firms to meet all reasonable requests for the installation of a phone line regardless of where in the UK a customer lives.
Phone services offered via that line must also be offered at the same price as any other line.
The two firms must also offer reduced rates to people on low incomes and provide a network of pay phones for people to use.
Now Oftel has updated these regulations to include a line capable of supporting dial-up net access at a speed of at least 28.8kilobit per second (kbps).
The fastest modems run twice as fast as this, but Oftel decided that this was the minimum that people should expect.
"This is significantly faster than the previous requirement of only 2.4 kbps and will lead to real improvements in connection speeds for many consumers," said David Edmunds, director general of Oftel.
Any customers who cannot connect at this speed have grounds for a complaint and BT and Kingston must make reasonable efforts to improve the service.
Oftel has also published new regulations that affect other telephone firms that cover the types of service that they must all offer, the publishing of easy to understand information for consumers, minimum contract terms and when they can disconnect a customer.