Enter valid prices for both plans and a whole-number period of 1–120 months to see the comparison.
How the estimate is worked out
Total = upfront cost + starting monthly price × comparison months + the monthly increase × months affected + any included exit fee. An increase starting in month 7 affects months 7 to the end of the chosen period, inclusive.
The tool models one specified permanent monthly increase per plan. It does not predict inflation, multiple annual changes, promotional discounts, partial-month billing, roaming charges or cashback. Enter zero where no charge applies and use a provider's full schedule if there are several changes.
Compare like for like
Use the same comparison period for both options and check that data, coverage, calls, texts and important extras are suitable. A lower total is not a recommendation if one plan lacks the service you need.
Include any relevant exit fee once in the option that incurs it. If you leave within a minimum term, obtain the actual charge from the current provider rather than estimating it from the remaining months.
Frequently asked questions
Are my figures saved?
No. Calculator values are held only in the current page and reset when it is reloaded. They are not sent to a service or stored.
Does it predict future price rises?
No. You enter one known increase and its starting month from the contract summary.
Can I compare a rolling plan with an annual plan?
Yes, over the same chosen period. A rolling price is not guaranteed to stay unchanged, so the estimate depends on your assumptions.
Does it include cashback?
No. Compare guaranteed payments first and consider conditional cashback separately.
Is the result a provider quote?
No. It is arithmetic based on your inputs; confirm the agreement and final bill with the provider.
Official sources
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Listings are dated snapshots of providers' own pages, not live prices, and CompareDirect does not sell the products we list. We are not a credit broker or lender and give no financial advice.