Quick answer
- Use the outstanding balance and remaining term, not the original mortgage.
- Compare both monthly savings and total cost over the same period.
- Subtract legal, valuation, break and other switching costs.
- Cashback can help upfront but should not hide a higher long-term rate.
On this page
The correct switcher calculation
Start with the current outstanding balance, current rate and remaining term. Run the same balance and term at the proposed new rate. The difference gives an estimated monthly saving before costs.
Do not restart a 20-year remaining mortgage over 30 years and call the lower payment a rate saving. That may reduce the monthly amount while increasing the time in debt and total interest.
Worked switching example
For €250,000 with 20 years remaining, an illustrative payment is about €1,582 at 4.50% and €1,450 at 3.50%: roughly €132 monthly difference. If one-off net switching costs are €2,000, the simple break-even is about 16 months.
Switching cost worksheet
| Add as a cost | Subtract as a benefit |
|---|---|
| Current-lender break fee | Cashback actually retained |
| New valuation | Legal-cost contribution |
| Solicitor and outlays | Other confirmed credit |
| Product or account fees | — |
| Protection replacement difference | — |
Divide net one-off cost by monthly saving for a simple break-even month. Then check total cost over the fixed period and full remaining term.
Cashback and break-fee warnings
Cashback is visible on day one; a rate difference compounds for years. Compare the new product with and without the incentive and read any retention, current-account or clawback condition.
If the current mortgage is fixed, request a break-fee quote before applying. It can change with market conditions. Also check whether waiting until the fixed period ends produces a better net result.
Eligibility and switching sequence
- Check current balance, LTV, rate end date and early repayment charge.
- Estimate the property value and likely LTV band.
- Compare like-for-like rates, APRC, fees and fixed periods.
- Check income, affordability, credit and property eligibility with the new lender.
- Confirm mortgage protection can be reassigned or replaced before cancelling it.
- Use a solicitor for the legal transfer and keep paying the existing mortgage until completion is confirmed.
Frequently asked questions
How do I calculate mortgage switching savings?
Compare the same outstanding balance and remaining term at current and new rates, then subtract all one-off costs and incentives.
How long should be left to switch a mortgage?
There is no single cutoff. The balance, remaining term, rate saving, costs and lender criteria determine whether switching is worthwhile.
Will switching restart my mortgage term?
Only if you choose a longer new term. Keep the existing remaining term in the first comparison to avoid disguising extra interest.
Are cashback mortgages cheaper?
Not necessarily. Compare the rate and total cost over the fixed period and full illustration after applying cashback once.
Can I switch before a fixed rate ends?
Yes, but a break fee may apply. Obtain a current quote and compare switching now with waiting.
Do I need new mortgage protection when switching?
You may be able to reassign suitable individual cover, while group cover may end. Confirm replacement or reassignment before completion.
Sources & references
Related calculators
Use these tools for the numbers behind this guide.