John Healey is reportedly preparing a tax crackdown on online marketplaces in his first budget, with a measure aimed at businesses such as Amazon and eBay that could bring the Treasury up to £1bn in additional revenue.

Under the reported proposal, marketplaces would have to collect VAT at source for every retailer using their platforms whose annual turnover exceeds £90,000. The measure would place responsibility for collection on the marketplace for sellers meeting that threshold.

The proposal therefore concerns both the retailers covered by the turnover test and the platforms through which they sell. Amazon and eBay are identified as examples of businesses at which the measure would be directed, rather than as an exhaustive list of marketplaces that could be affected.

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The potential Treasury gain is described as up to £1bn more. That figure is an upper estimate of additional revenue, not a guaranteed receipt. The limited information available does not establish the period over which the money would be raised or provide a breakdown of the estimate.

The £90,000 figure has a different function: it is the annual-turnover threshold for retailers whose VAT would be collected by the marketplace. It is not a proposed tax payment, nor is it presented as a turnover test for Amazon, eBay or other platform operators themselves.

As described, the requirement would cover all retailers on a marketplace with turnover above that threshold. The reported wording does not limit the collection requirement to particular categories of goods or identify a narrower group of qualifying sellers.

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The distinction between collecting a tax and changing its rate is also important. The reported measure addresses who would collect VAT at source. The supplied details do not identify a proposed change to the VAT rate, so the potential revenue gain cannot be characterised as the result of a rate increase.

The information available is insufficient to assess the practical demands on marketplaces or the effects on individual retailers. It contains no responses from Amazon, eBay or affected sellers, and provides no detail on how platforms would establish which retailers fall within the requirement.

Healey’s first budget is the reported setting for the proposed crackdown. Until fuller details are available, its implementation and revenue implications remain uncertain: the central reported elements are marketplace responsibility for VAT collection, the £90,000 annual-turnover threshold and a possible Treasury gain of up to £1bn.