More than $129.5 million has been paid through the Covid-19 Leave Support scheme to employers to cover staff forced to isolate.
It comes amid calls from the Greens to expand the scheme's tight criteria so it can be accessed by companies whose staff need to stay home while waiting for a test result but don't have enough sick leave.
Currently only people who test positive, contacts of confirmed cases or those who do a high-risk job and cannot work from home are eligible to have their leave covered by the Government fund.
Employers who access the scheme must endeavour to pay their staff on leave 80 per cent of their normal wages and the subsidy is $585.80 per week for full-time workers and $350 for part-time staff.
Data from the Ministry of Social Development reveals there have been 24,247 approved applications covering about 90,000 workers since the scheme's inception in March during lockdown until November 6.
Of those applications, 19,641 applications were paid to employers and a further 4,606 paid to self-employed. The total paid out amounted to $129,448,173.
The Green Party's workplace relations spokesperson Jan Logie wants the criteria expanded further so workers are eligible if they have Covid-19 symptoms and have to isolate while awaiting their test results.
Logie was concerned thousands of casual and seasonal workers starting new jobs over summer in industries like horticulture, retail and hospitality would have little to no annual or sick leave accrued to fall back on.
"Many seasonal workers who get sick over summer will be put in the position of choosing between paying the bills or taking unpaid leave to self-isolate while they await a Covid-19 test."
Retail Association chief executive Greg Harford said most employers were footing the bill for their staff to stay home if they needed to but didn't have any leave left so supported relaxing the schemes criteria so businesses could access more support.
And with the Government ruling out doubling sick leave entitlements by Christmas, Logie said relaxing criteria for the leave scheme would come at "small extra cost" compared to the cost of community transmission.
Workplace Relations and Safety Minister Michael Wood said he'd requested advice on whether the scheme was meeting its objectives and if not, what options there were to improve it.
"I'm now in discussions with other ministers so it's a little too early to say where that might go but we're open to options to make sure that the scheme is providing as much support as needed."
Until then he urged workers and employers "to work together" to ensure staff could stay home if and when needed.
"This whole year we've had this challenging situation and employers and employees have done pretty well for the most part."
The National Party's workplace relations spokesman Scott Simpson said he supported the current criteria of the leave support scheme but the figures of how much it has cost "starkly highlight" how costly the burden of Covid-related employee leave had been.
The price tag of the scheme revealed the impact doubling statutory sick leave entitlements would be to businesses.
"The Labour Government's natural instinct is to comply with demands from trade unions but to have little or no concern for inflicting extra costs on employers."
Wood this week introduced legislation to boost sick leave entitlements from five to 10 days but it will go through the full select committee process and will likely come into effect late next year.