Azure showed $21k in startup credits. Claude in Foundry billed our card $17k

Vegalabs AS, Norway. October 2026.

Credit remaining in the sponsorship portal, 7 September

USD 21,168

Invoiced to our credit card, 11 August to 7 September

about USD 17,600

Since March, at least ten startups have publicly reported the same thing. They deployed Claude in Microsoft Foundry on Microsoft's startup credits, and their credit card was charged instead. Microsoft updated its documentation. Seven months later the portal still let it happen to us, and our bill is about USD 17,600.

We are two people in Norway running a small software company, Vegalabs AS. Microsoft accepted us into Microsoft for Startups and gave us USD 25,060 in Azure credit. In August we deployed Claude in Microsoft Foundry, next to the GPT models we already ran on those credits.

We used it for an experiment: can a model find patterns in five years of stock exchange data? That means large inputs and long, deep analyses. We ran it because we had the credits. More than USD 21,000 sat unused and would expire in September, and this looked like exactly what the credits were for.

Four weeks later Microsoft tried to take about USD 16,500 from our credit card. The invoice now stands at about USD 17,600 before VAT. Microsoft bills us in Norwegian kroner, so the dollar amounts here are converted at roughly 9.6 kroner to the dollar. The day after we found out, our sponsorship expired with USD 21,168 of credit unused.

Microsoft says only Anthropic can approve a refund. Anthropic says there is no approval for it to give, and that the decision is Microsoft's. We have both statements in writing. Four of the seven replies we received were written by AI.

What we got wrong

The rule is documented. Microsoft's sponsorship coverage page lists Anthropic among the providers that startup credits do not cover. The sponsorship offer terms exclude Marketplace products. We read neither page before deploying. We had no budget alert on actual cost, because we took the credit balance for the cost.

That part is on us, and we have said so to Microsoft in writing. We do not dispute the usage. We acted in good faith, and we deleted the deployment within the hour once we saw where the bill was going.

Our complaint is about two other things: what the product showed us while the meter ran, and what happened when we asked for help.

What the portal showed us

Nothing in the product separated Claude from the models our credits paid for. We have screenshots of each point below.

One list. In Foundry's model deployments view, claude-fable-5 sat in the same table as gpt-4o, gpt-5.4-nano and o4-mini. Same resource, same columns, same content filter. No label marks it as a Marketplace product billed to a card.

GPT usage drew down credit. The sponsorship portal listed our GPT token usage line by line against the credit. Claude never appeared there.

A healthy balance. On 7 September the sponsorship portal showed USD 3,892 used and USD 21,168 remaining, with one day left on the offer.

The real cost sat in another view. Cost analysis, filtered on Marketplace invoices, showed August at 126.8K kroner, about USD 13,200. All of it is labelled "SaaS" and "global". Claude is not named.

No notification. No email, alert or banner while the Marketplace charges built up. Our card issuer was the one that reacted: it declined the charge as suspected fraud.

The detail that bothers us most is in Microsoft's own Claude deployment guide. It lists "Sponsored subscriptions that only use Azure credits" as not supported for Claude. It then adds that if a credit card is on file, the card is charged instead of the credits.

So Microsoft knows this subscription type should not run Claude. The portal deployed it anyway and sent the bill to the card. A block at that step, or one line of warning, would have cost Microsoft nothing.

To be fair: Microsoft's guide says the deploy flow asks you to accept Azure Marketplace terms. Neither of us remembers that dialog. If it was there, it did not tell us that our credits would not apply or that our card would be charged.

The loop

The two companies gave us answers that cannot both be true.

Microsoft Startup Support, 9 September:

If Anthropic approves the request, they can initiate the appropriate refund authorization through Microsoft.

Anthropic support, the same evening:

There is no publisher authorization step required from Anthropic for Microsoft to process refunds on their platform.

We sent Anthropic's answer straight back to Microsoft. Startup Support closed the case and told us to open a new one with billing. Azure Billing then sent a careful, human reply. It acknowledged that the billing behaviour "may not have been obvious during deployment", and it sent us back to Anthropic.

We asked for one thing after that: escalate to the Microsoft for Startups program team and tell us if a payment plan exists. Five minutes later an AI-generated email said the request was out of scope. That was 15 September. Nobody has answered since.

Two details from the Anthropic side. Both replies came from an AI agent, the first in under three minutes. Both called our subscription an "Azure Student Sponsorship". We are not students, and no human at Anthropic has replied.

One detail from the Microsoft side. The coverage page ends with a rule of thumb: if Microsoft bills the model usage to your Azure subscription, the credits apply. Anthropic's written position is that Microsoft bills this usage. We do not think Microsoft means what that adds up to. It does show how unclear this is, even on the page written to clear it up.

This has been public since March

We are at least the eleventh documented case, and Microsoft has known about the pattern for seven months. These are the ones we found in an afternoon:

The Register covered this on 13 March and again on 19 March, and asked Microsoft for comment. Microsoft answered that it listens to feedback and keeps working on clear guidance in its documentation. There is also a petition from affected founders.

Microsoft did update the documentation. The coverage page naming Anthropic is dated March 2026. The product is another matter: in August the portal still let a sponsorship subscription deploy Claude, with no label and no warning.

The first row matters for a second reason. Microsoft has already granted a credit as a special exception in this exact situation. So the discretion exists. We have not been able to reach anyone who holds it.

What we are asking for

1. Microsoft: one person with the authority to decide. USD 21,168 of sponsorship credit expired unused on 8 September. Apply it to invoice G183358345, or waive the invoice.
2. Anthropic: a reply from a human, and one written sentence to Microsoft that settles whether publisher approval exists.
3. Both: fix the product. Block Claude deployments on sponsorship subscriptions, which the documentation already calls unsupported. Or show one line before deploy: not covered by your credits, your card will be charged. And show Marketplace spend next to the sponsorship balance.

If you are on startup credits yourself: only the "Direct from Azure" collection in the Foundry catalog is covered. Set a budget alert on actual cost, since the credit balance will not move when Marketplace charges accrue.

A bill this size is more than a small company like ours can absorb. It also puts an unrelated product at risk: our production service runs on the same Azure subscription, and Microsoft can suspend that subscription over an unpaid invoice. We will update this post with whatever either company answers.

Appendix: the timeline

All times are from the email headers. Ticket numbers are available to Microsoft and Anthropic on request.