@MuthuKasi-MSFT You might be checking this from the Azure portal. Storage size for business-critical instances would depend on the hardware generation –
- Standard-series (Gen 5) with 80 vCores supports 4096 GB of storage.
- Premium-series with 128 vCores supports 5632 GB of storage.
- Premium-series memory optimized with 128 vCores supports 16384 GB.
Resource limits - Azure SQL Managed Instance | Microsoft Learn
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