The ISP and telephone operator claims half a million homes a year are tricked into signing with another operator. The scheme, known as 'slamming' relies on a salesman claiming to be from BT when they're in fact from a completely different operator.
BT says the pin-code scheme would see homes requesting a pin from their current supplier, which they then pass on to their new supplier, if they want to switch providers.
"The process we're proposing will put an end to mis-selling misery for good, protect consumers and safeguard fair competition," said John Petter, managing director of BT's consumer division.
"Ofcom's own data shows that a consumer protection pin code would eliminate mis-selling."
Earlier this year, Ofcom unveiled a new set of proposals to tackle 'slamming'.
Under the proposals any telephone operator found guilty of 'slamming' tactics will be liable for a fine of up to 10 percent of their total turnover.
The proposals also require telecom companies to keep records of telephone conversations with customers as well as agree to not 'engage in dishonest, misleading, or deceptive conduct'.
However, Ofcom revealed it has doubts over BT's proposed scheme.
A spokesman told the BBC: "We have concerns that a process which requires consumers to contact their existing provider before they switch [such as a pin based process] may impede switching and the benefits to competition which flow from easy consumer switching processes."