Porting mortgage and additional borrowing/extending term

roofoxy14

Hi all, 
Could anyone help me wrap my head around this?
Current mortgage has 2 years remaining  on the fixed term. (12 years til finished)Hoping to achieve £120k sale and current balance is £60k.

New property is £195k. 

If I port my mortgage I would need to borrow the additional and extend the term to 20 years on the additional amount.

How would I calculate the monthly amount I will be paying? 
Existing rate is 4.25%
New rate would likely be 4.75%
(I know this is something that can be discussed at my next mortgage appointment but I need an idea of what the payments will before I make an offer and the mortgage lender needs us to have an offer accepted before we can have the next appointment!)

Any clarification would be appreciated 

kingstreet

Why are you leaving the existing borrowing on that short term? Why not have a longer term for both tranches of borrowing?

Either way you need to do two calculations. One for each tranche, then add the two payments together.

For example;-

£60,000 @ 4.25% over 15 years = £450.82 +
£75,000 @ 4.75% over 15 years = £582.61

Total monthly cost = £1,033.43

roofoxy14

Thankyou for the reply.
When we got our mortgage in principle they did mention something about extending the term of the original mortgage but they didn't really explain it, they were more focused at that appointment on affordability.
This makes a lot of sense, thankyou