Fair play on the healthy savings habit, 37k is a substantial sum. However, it really doesn't make sense to hold onto such large savings while continuing to pay down more expensive debt. If you're thinking of trading up in the future you will need to sell your house anyway, so you should recover any extra equity you build up in your home by overpaying your mortgage.
I'm no expert but in your situation I'd be considering the following:
-> Hold onto your 7k in BoI as an emergency fund
-> Stop saving and increase your monthly mortgage repayments to whatever you can afford (look at it as just another type of saving)
-> Keep your mortgage on a variable rate to allow you the freedom to make extra lump-sum contributions without penalty
-> Once your term savings a/c matures next March I'd pay a lump sum of around 25k off the mortgage, leaving savings of around 12k. Keep half those savings in an instant access a/c and the other half in a 30-day notice a/c (shop around for best rates)
-> This should leave you with a mortgage balance of <40k
Paying off your mortgage faster has major advantages
- It's a tax-free investment
- It's risk-free
- If your interest is calculated daily you'll see an immediate interest return, i.e. you'll be paying less and less interest and more and more off the capital
- It gives you additional peace of mind and financial security. Your reduced exposure means you'll need less insurance, for instance you may be able to reduce your life cover, saving you more money.
The downsides are
- You won't see your money again until you sell your property
- Newer/younger buyers may forfeit some of their govt. tax relief on their mortgage interest. That won't apply in your case.
- The opportunity cost of being unable to make potentially more lucrative investments. However, remember that such investments invariably involve a) risk and b) tax
Re. fixed vs. variable rates, this is a personal choice and depends on your attitude to risk and the rates on offer. However, bear in mind that you do not have a big mortgage, so the risk to you from future interest rate rises (the main argument in favour of fixing) is relatively modest. Also, fixed rates can be quite expensive. Personally, I wouldn't be bothered fixing, especially as you're in a position to pay such a large lump sum off the mortgage next year.
Disclaimer: the above are the views of a non-expert. It's always a good idea to get professional, independent financial advice.