The migration itself is small. In JavaScript, developers replace the AccountBalanceQuery import with MirrorNodeAccountBalanceQuery and keep the same setAccountId and execute pattern. Java and Go follow flows. Rust, Swift and C++ applications can still access the same balance data directly through the Mirror Node REST endpoint using the client’s mirror-network configuration. The change reduces migration friction while aligning account-balance reads with Hedera’s Mirror Node architecture and its open-source SDK ecosystem.
The shift is mandatory for applications that depend on AccountBalanceQuery. Hedera said the consensus-node endpoint behind that query is throttled to zero on testnet and mainnet as of Consensus Node software v0.77. Developers must therefore update to a recent SDK release and replace the deprecated query. Applications that do not use AccountBalanceQuery are unaffected. The deprecation makes Mirror Node migration an operational requirement rather than an optional optimization for affected applications, reinforcing the role of Mirror Node infrastructure.
There is one timing consideration. Mirror Nodes receive data from consensus nodes after propagation, which can take several seconds. Hedera recommends adding a short retry or polling step when reading a balance immediately after submitting a transaction, or relying on the transaction receipt. Developers are encouraged to test MirrorNodeAccountBalanceQuery against a testnet account before deployment. The new method gives applications a supported migration path while keeping balance reads inside Hedera’s native SDK experience.
