Re-mortgage offers with current lender now cheaper than other mortgage lender I'm borrowing from

surreygirl

My teensy rate HSBC mortgage is due to end 1st November, and they wanted another £350pcm to revert to SVR - and on checking their deals in July they offered nothing better. I went through a mortgage broker I've used previously and she found a rate of 5.59% in July from Santander which would 'only' cost me £200pcm more than my previous £1330pcm - this deal was much lower than other rates at that time. 
The mortgage deeds form has been signed, free legal cover offered by Santander taken, and just waiting now for the final documents ahead of the change in 4 weeks time - but HSBC has now dropped their remortgage rates to a better deal - which would theoretically reduce my new monthly cost from £1530 to £1490 - not insignificant. 
I am tied to the Santander offer? Or can I say 'thank you - but no thank you' to them and stay with HSBC - if the rates they say they'll offer will be honoured? Or should I ask Santander to reconsider their interest rate offer, which is still not competitive if you check their site. Any help appreciated

Edi81

I’d be looking at the contract you signed with the broker first. Does it say anything about fees payable if you don’t complete? They will be getting commission from Santander which they won’t get if you stay with HSBC. 

silvercar

Go back to your broker, tell them what your current lender are now offering you and let them do the leg work. It may be that the new lender also has a new rate or the broker can find you something elsewhere.

ACG

Rates have been coming down since July. 
It could be that Santander have also lowered their rates.