Step 1: Call your current insurance company and find out what they would charge you to cancel your policy in addition to your regular premium costs.
Step 2: Take your current policy premium and divide it by 12. If you pay for your insurance in monthly instalments, just use the monthly payment. Now multiply that number by the amount of months you have left on your policy. Write this number down, as you'll need it in Step 4.
Step 3: Now take the premium total from the new company's policy and divide it by 12. Then multiply it by the number of months you have left on your old policy.
Step 4: Take the final number from Step 3 and subtract it from your final number in Step 2. This represents your total savings over the remaining months of your policy.
Step 5: If what you are saving is less than your cancellation fee, there is no point in your switching companies until your current policy expires. If the savings were higher than your cancellation fee, you'd be better off switching as soon as possible!