The digital adviser is to start sending alerts to borrowers who are six and three months from the end of their term when they sign up for the service.
Dynamo found mortgage holders spent 42 days on average on SVRs after their deal has expired.
The adviser has now launched a mortgage alarm clock to help people who sign up switch deals before it’s too late.
Seb McDermott, chief executive officer at Dynamo, said: “The research shows that far too many people are not switching mortgage deals in time.
“We strongly urge mortgage holders to give themselves enough time to find their next remortgage and that’s why we have launched our Dynamo Mortgage Alarm Clock.
“We typically recommend people start their search around four months before their current deal is due to expire.”