The platform bills through one prepaid wallet per workspace. You top the wallet up in euro and spend it on any backend — simulator runs are free, real QPU shots and GPU/CPU minutes draw from the balance. 1 credit = €0.01. There are no surprise charges: every paid run reserves its worst-case cost from the wallet before it is submitted and settles the actual cost when it finishes (see cost safety).

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Who can pay

Only workspace owners and admins can top up credits, purchase plans or change spend limits. Developers and viewers get 403 on billing actions. See the roles matrix.

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Top up credits

1

Open Billing

In the console, open Billing. The page shows your available balance and currently reserved credits.
2

Pick an amount

Use a preset — €50, €150, €500 or €1,000 — or enter a custom amount. Custom top-ups are accepted between €0.01 and €50,000.
3

Pay in the embedded form

Payment is collected in an embedded Stripe Payment Element — you never leave the console. Euro payments accept card, SEPA debit, iDEAL and Bancontact.
4

Credits land instantly

Once the payment succeeds, the credits are added to the workspace wallet and an invoice is recorded. Credit grants are idempotent — a retried payment webhook can never double-credit you.
The balance is available programmatically too:
Historical field names use a Usd suffix (prepaidBalanceUsd, amount_usd). The number is your wallet balance; 1 credit = 0.01 of it. The SDK’s qc.credits() and the CLI’s qcoscloud credits read the same field.

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Spend limits and budgets

  • Soft and hard monthly limits — configurable per workspace by owners/admins with PATCH /api/v1/platform/billing/limits (body: {"softLimitUsd": ..., "hardLimitUsd": ...}). Both are shown on the Billing page next to the month’s usage.
  • Per-run guardrails — max_estimated_cost_usd, max_shots, max_actual_charge_usd, max_runtime_seconds on each submission. See Run workloads.
  • Workspace budgets — a workspace can additionally carry a rolling daily or monthly execution budget; runs that would exceed it are refused with daily_budget_exceeded / monthly_budget_exceeded (HTTP 402) and nothing is charged. See Errors.

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Plans and licenses

Billing also lists the platform plan catalog (GET /api/v1/platform/billing/plans): platform access, compute credit plans and QuantumLock licensing. Purchases use the same embedded Payment Element flow, and license purchases activate the corresponding entitlement for the workspace (see the Licenses page in the console).

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Invoices

Every top-up and purchase produces an invoice. The Billing page lists the workspace’s invoices (also GET /api/v1/platform/billing/invoices, most recent 50) with period, amount, status and — where available — a PDF link.

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The credit ledger

For a per-job accounting trail, GET /api/v1/platform/usage/ledger returns the workspace’s immutable credit ledger: one entry per reservation, settlement debit and release, with units, cost and the balance after each entry. The Usage page presents the same data with per-backend and per-type breakdowns.

Backends & pricing

What each backend costs and how reservations settle.

Refusal reasons

insufficient_credits and every other money-related refusal.