The Electoral Commission says it is confident there won't be another major outage of its electronic electoral roll (eRoll) on election day.
At the last general election its eRoll - a mobile app which polling booth staff use to search the live electoral rolls - went down for nearly four hours in a crash that the Commission soon after found was ultimately avoidable.
The outage happened at a time when many voting centres were already under strain with large queues, and some people were reported to have left the queues before voting due to the wait.
"Since voting opened the Commission’s eRoll application has operated without major issue, reflecting significant work undertaken to strengthen its performance and reliability," the Commission said.
That work included increasing server capacity and carrying out multiple rounds of performance testing.
It has prepared for up to 85,000 eRoll look-ups an hour on Saturday.
"These changes have strengthened reliability, streamlined processes at voting places and delivered a more consistent experience for staff and the public," the Commission said.
Review recommended changes
In response to an Official Information ACt request (OIA), the Commission said that reviews following the 2023 general election recommended changes to load testing requirements and assurance, improvements to incident management processes and increased collaboration between suppliers and the Commission during application change and design.
“While the root cause of the technical issues was understood and resolved as part of the initial response, and it was recognised that these improvements would be required to ensure similar problems are not experienced in the future,” the Commission said.
By the end of October 2023 it had doubled web server capacity, removed unnecessary SQL queries and reduced the frequency of automated reporting from hourly to every three hours.
More substantive changes followed in March 2025 when the Commission removed the ability to update voter details at voting places and improved staff scripts to reflect changes to enrolments.
June 2026 saw further improvements introduced to simplify searching for elector details and reduce user errors at voting places.
In September 2026 it updated enrolment closure dates in line with the Electoral Act Amendment, introduced a dedicated process to generate special votes when voter details could not be matched, and made plain-English improvements for a more consistent user experience.
System tested against higher than expected demand
For the 2026 election, the Commission forecast peak demand of approximately 85,000 eRoll look-ups an hour, based on expected voter turnout and election day voting patterns.
Using that modelling, it had set its performance testing target at 170,000 requests an hour – twice the forecast demand.
"Testing confirmed that the application can run above estimated transaction volumes, while maintaining acceptable response times," the Commission said.
Documents released under the OIA show the Commission has carried out several rounds of load and performance testing since the 2023 election, with two tests that reached the forecasted volumes, both in July 2025 ahead of the Tāmaki Makaurau by-election.
In one test, the system recorded 138,000 transactions an hour against a target of 85,000, in another, it recorded 261,861 transactions an hour against a target of 300,000.
Another test was done in 2026 following an update, but at a lower volume.
Further load and performance tests were expected to have been completed ahead of the election that were not included in the OIA response.
One minor issue during voting this election
The Commission said on the first day of advanced voting it identified a "minor" problem that meant the eRoll did not display the right information in some circumstances.
"We made a change that day to the way information was displayed. Voters were still issued with the correct ballot papers," the Commission said.
Backup plan if the system fails
The Commission also released its Voting Place Business Continuity Plan under the OIA.
The two-page document outlined how polling booth staff should direct voters to the correct queue if eRoll becomes unavailable.
The Commission said the plan was tested in April and June.
SHARE ME