@Richard Howell ,
Thank you for reaching out to the Microsoft Q&A platform. Happy to answer your question.
When you register for a free Azure account, you will get $200 free credit toward Azure products and services, plus 12 months of popular free services - https://portal.azure.com/#blade/Microsoft_Azure_Billing/FreeServicesBlade
After 30 days (or consumption of $200), you are supposed to convert your free trial account to a pay-as-you-go account. if you want to move to pay-as-you-go pricing, enabling you to purchase Azure services beyond free amounts. If you do, you will keep getting access to all the free services. If you do not, your account and services will be disabled.
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