What is GEM?

GEM is an energy tracking and reporting tool that gives you greater visibility of your household energy usage and the opportunity to reduce your energy consumption and cost (‘GEM Service’). 

How do I access the GEM Service?

To access the GEM service, log-in to My Account on the Mercury website ( By using the My Account service, you agree to receive the full range of GEM Services that we may from time to time offer as well as agreeing to these GEM Terms and Conditions.   

Who is GEM available to?

Not all GEM features are available to all customers or all types of electricity meters. The type of GEM features available are largely dependent upon what type of meter you have; a smart meter or another type of meter.
Even if you don’t have a smart meter, you can still experience many of the benefits of GEM:

  • Track your monthly usage and monthly costs
  • Compare your bills with previous months and the same bill last year
  • Compare your home against similar-sized homes nearby
  • View personalised energy saving tips and set a goal to see how you’re tracking


What are GEM’s features?

Projected Bill Estimate
Your past energy usage is not necessarily a reliable predictor of future usage. Your actual bill will differ from your projected costs as your bill is based on your actual usage, current energy prices and any other charges.  Data may be estimated if actual meter reads are unavailable. The amounts shown include GST and assume that you have or will receive Mercury's Prompt Payment Discount, even if you did not or will not receive that discount, for the period shown. The projected bill estimate is a feature available to customers with smart meters.

Usage Details
The amounts shown in the cost view include GST and assume that you have received Mercury's prompt payment discount, even if you did not receive that discount for the period shown.
The daily and half-hourly views are only available to smart meter customers and only show the variable cost component and do not include the daily fixed charge. Please be aware of this if comparing against your total bill. Data may be estimated if actual meter reads are unavailable.

Bill Comparisons
Bill comparisons are based on your actual usage and current energy prices at the time of each bill and do not account for any price plan changes.  The amounts include GST and assume that you have received Mercury's Prompt Payment Discount, even if you did not receive the discount for the period shown. Data may be estimated if actual meter reads are unavailable.  Bill comparisons are available for all customers. 

Saving Tips
Tips offer general information about potential efficiencies and savings that could be achieved in a typical household in New Zealand. These tips are not specifically tailored to any individual, home, or appliance. Actual savings and efficiencies may vary subject to your personal circumstances, including individual appliances, how you use them, current energy prices and your household's consumption. To learn more about some of the key sources used to develop these tips, please visit  Savings tips are available for all our customers to view. 

Emails and Paper Reports
Weekly and monthly GEM emails and/or quarterly paper reports featuring additional information may be offered to you for further information on your usage.  These additional features may from time to time be offered to you as a free trial, as and when determined by Mercury. Otherwise, a fee may be charged for these additional information services. 

Any fees will only be charged with your consent and are inclusive of GST. Fees will be added to your Mercury bill on monthly or quarterly basis, as appropriate.

You understand and accept that Mercury has the right to withdraw any of these additional GEM features and/or any free trials it may offer in relation to these additional features, at any time and at its sole discretion.  Additionally, Mercury may change any fees it charges in relation to these additional features at any time, provided that where fees increase, we will give you 30 days notice before charging you the fee increase for features that you have subscribed for.  You may cancel your subscription to any additional GEM features at any time by calling 0800 677 847 or by changing your GEM Options through My Account at

When will I get a smart meter?

At present the majority of residential customers and over half of business customers have smart meters. 

Changes to GEM Services and these Terms and Conditions 
We may at any time modify, add to or suspend the GEM Services, the way you access the GEM Services or any of these GEM terms and conditions, by notifying you of any changes via email, by posting information on our website, or any other means.  If we amend these Terms and Conditions, your continued use of the GEM Services will indicate your agreement and acceptance of those amendments.

We have taken care to ensure that the information provided in GEM is as accurate and reliable as possible, but, mistakes may occur.  To the extent permitted by law, Mercury is not liable for any inaccuracy in the information contained in GEM.