How do I compare mobile plans?

Compare the total cost over a year, including the monthly plan and any device repayment, not just the monthly figure. A cheap plan with a pricey phone on top can cost more overall.

Is it cheaper to buy a phone outright?

Often yes, because buying outright and using a low-cost plan can beat a bundled plan with the device built in. Comparing the total cost reveals the difference.

What should a phone plan include?

Enough data and calling for your use without paying for far more than you need. Match the plan to your real usage to avoid overpaying.

Phone Plan Comparison Calculator

This calculator works out the true annual cost of two mobile phone plans side by side, so you can see which one actually costs less once a device repayment is included, not just which has the lower headline monthly price. Phone plans in New Zealand are often bundled with a device, and a plan that looks cheap on its own can end up costing more once the phone repayment is added, while a plain SIM-only plan on a cheaper network can work out ahead over a full year. You enter the monthly plan cost for Plan A and Plan B, along with any monthly device repayment attached to each, or none if you already own your handset. The calculator instantly returns the annual cost of each plan, the dollar saving between them, and a clear verdict on which plan is cheaper over a year, making it easy to compare a bundled plan against a bring-your-own-device SIM plan on a like-for-like basis. Remember that once a device is paid off, the ongoing plan cost usually drops, so a plan carrying a device can become more expensive relative to a SIM-only plan the longer you keep it, and a plan that looks worse today may pull ahead later. This is an indicative cost comparison based on the figures you enter, so check the actual contract terms and data allowances before switching providers.

Plan A

Monthly plan cost

Device repayment per month

Plan B

Monthly plan cost

Device repayment per month

cheaper plan over a year

Plan A per year$0

Plan B per year$0

Saving$0

Include any device repayment so a low plan with a phone on top is compared fairly. Once a device is paid off, the plan cost drops, so a plan with no device can win over time. Estimate only.

How it works

The calculator adds the monthly plan cost and any device repayment for each plan, then multiplies by twelve for the annual cost. Comparing the totals shows which plan is cheaper for a year, including the phone. A SIM-only plan often wins once you account for a device built into a bundled plan, especially after the device would have been paid off.

Worked example

Plan A at $40 a month with no device is $480 a year. Plan B at $20 a month plus a $35 device repayment is $55 a month, or $660 a year. Plan A is cheaper here, and even more so once any device on Plan B is paid off.

Related calculators

Broadband Cost Calculator: compare broadband.
Subscription Cost Calculator: recurring costs.
Budget Calculator: household budget.
Cost Per Use Calculator: value of a purchase.

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