Customers have shared their outrage after an app used by many businesses to track timesheets and produce invoices hiked bills by as much as 1500%, with one person calling it "daylight robbery".
Richard Haldenby, head of UK consultancy firm Salentis, told the BBC his monthly bill had risen from $130 (£95.50) to $2,110.
Others have reported similar price hikes online, with one person in the US saying their annual charge went from $2,800 to $23,000.
The BBC has approached Harvest for comment.
Harvest was acquired by the Italian tech company Bending Spoons in 2025, and changed its pricing structure the following year.
Many businesses who pay annually are only now finding out about the increase, as their payment is now coming up for renewal.
Haldenby, whose business consists of up to 15 staff in the UK at any one time, with sister companies also in the US and Australia, said he was "in shock" when he received an email detailing the price changes.
"We have used Harvest in our three companies for at least 15 years and have been loyal and enthusiastic advocates of it," he said.
"But if we were to accept this increase it would double our IT spend for the year, which is completely unaffordable."
Until the change, businesses paid a flat monthly fee for each user.
They could add or remove users as their staffing needs changed, meaning they only paid for the people who needed access.
Under the new usage-based pricing model, businesses can also be charged according to the number of active projects, clients and tasks they have - as well as the amount of revenue they invoice through the platform.
Haldenby said he contacted the company to say his firm would not accept the change.
He was then offered a discount for the next year - taking the price down to $1,309 - which would need to be paid up front.
But he said he believed this would just "delay the inevitable", so he is "planning to migrate to a similar but less good service".
"It's a classic example of corporate greed over valuing customers," he said.
The move has drawn criticism online, with one analyst telling the BBC it was "extremely bad practice".
"Harvest has completely failed at the transparency test," said Mark Peacock, head of the UK consultancy firm PriceMaker, which focuses on pricing strategy for small and medium-sized enterprises (SMEs).
"There is no way for a customer to work out how much it's going to cost them until they get their bill at the end of the month.
"Many users are reporting a 10-fold increase in costs which is entirely unacceptable."
Who are Bending Spoons? #
Damian Foks, head of consulting at Valueships, said the Harvest price hike was "a clear sign of a shift in the company's strategy from growth to monetization".
He said this was "likely" a result of the firm being taken over by new owners.
Bending Spoons has acquired more than 50 major tech firms since it was founded in 2013, such as Evernote, Vimeo and WeTransfer.
The business has a track record of raising prices in companies it has acquired in the past.
Following its 2022 acquisition of the note-taking app Evernote, the company implemented sharp subscription price increases alongside layoffs in the US and Chile.
Both WeTransfer and Vimeo have faced tighter limits on free tools since they were separately acquired by the Italian tech firm, with legacy users also forced to move onto more expensive pricing tiers.
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