The mutual said the changes would make the application process easier and more flexible for customers.
It said customers can start the mortgage application online and gain a mortgage approval in principle in their own time.
Once this is complete the customer will visit a branch or call the building society to complete the deal.
Yorkshire said this would give borrowers the assurance of having mortgage funding in place, but not committing them to a specific mortgage, loan size or term length.
The result is valid for 30 days and is subject to further checks once the application progresses.
Nick Gander, e-commerce manager for Yorkshire Building Society, said: “By giving borrowers the ability to begin their application online, then transfer to a branch or complete things over the telephone if they would like more guidance, they can do things when and how it suits them.”
At a financial services conference in May this year, brokers were warned that lenders were investing in technology which would help them to boost their direct-to-consumer sales. Speaking at the event, Robert Sinclair, chief executive of the Association of Mortgage Intermediaries, said game-changing technology from banks would hit the market in 18 months to two years’ time.