SUBMIT A PRSUBMIT AN ISSUElast edit: Mar 31, 2026

Batch Transactions

The Bittensor runtime's utility pallet exposes three extrinsics — batch, batch_all, and force_batch — that let you submit multiple calls as a single on-chain transaction. This is useful when you want to stake to multiple hotkeys, perform multiple operations atomically, or reduce the number of round-trips to the chain.

For how fees are calculated across a batch. See Batch Transaction Fees.

batch vs batch_all vs force_batch

The three variants differ only in how they handle errors. Choose based on whether partial success is acceptable:

Extrinsic	On error
batch	Stops at first failure; prior calls succeed. Emits BatchInterrupted.
batch_all	Reverts all calls atomically on any failure.
force_batch	Continues past failures; failed calls are skipped.

info

Use batch_all when all inner calls must succeed or none should. Use batch if partial success is acceptable, or force_batch to continue past failures.

Source code: batch pallets/utility/src/lib.rs:197–201, batch_all pallets/utility/src/lib.rs:309–313, force_batch pallets/utility/src/lib.rs:408–412.

Using batch calls with the SDK

Use a proxy coldkey for these operations

The operations on this page require a coldkey. Your primary coldkey should remain in cold storage (hardware wallet) and never be loaded onto a machine running btcli or the Bittensor SDK. Use a scoped, delayed proxy coldkey to perform these operations via btcli or the SDK. See Coldkey and Hotkey Workstation Security and Proxies.

The SDK's add_stake_multiple and unstake_multiple send individual extrinsics sequentially, not a single batch extrinsic.

To submit multiple stake actions as an atomic batch (one extrinsic on-chain), use the low-level pallet builder + proxy path. The batch call is wrapped in a proxy extrinsic signed by your proxy wallet.

Proxy type for batch calls

The Staking proxy type is an allowlist of specific staking extrinsics. It does not permit Utility::batch_all as the outer call, so batch staking via a Staking proxy will fail with CallFiltered. Use a NonTransfer proxy for batch staking. NonTransfer blocks only balance transfers and coldkey swaps, allowing everything else including batch wrappers. NonCritical also works but is more permissive than most users need.

import os
import bittensor as bt
from bittensor.core.chain_data.proxy import ProxyType
from bittensor.core.extrinsics.pallets import SubtensorModule

sub = bt.Subtensor(network="test")
proxy_wallet = bt.Wallet(name=os.environ['BT_PROXY_WALLET_NAME'])
real_account_ss58 = os.environ['BT_REAL_ACCOUNT_SS58']

hotkey_1 = "5GrwvaEF5zXb26Fz9rcQpDWS57CtERHpNehXCPcNoHGKutQY"
hotkey_2 = "5FHneW46xGXgs5mUiveU4sbTyGBzmstUspZC92UhjJM694ty"
netuid = 1
amount = bt.Balance.from_tao(10)

pallet = SubtensorModule(sub)
call_1 = pallet.add_stake(netuid=netuid, hotkey=hotkey_1, amount_staked=amount.rao)
call_2 = pallet.add_stake(netuid=netuid, hotkey=hotkey_2, amount_staked=amount.rao)

# Wrap in Utility.batch_all — reverts all calls atomically on any failure
batch_call = sub.compose_call(
    call_module="Utility",
    call_function="batch_all",
    call_params={"calls": [call_1, call_2]},
)

# Submit via proxy — Staking proxy type cannot wrap batch calls, use NonTransfer
response = sub.proxy(
    wallet=proxy_wallet,
    real_account_ss58=real_account_ss58,
    force_proxy_type=ProxyType.NonTransfer,
    call=batch_call,
)
print(response)

add_stake_multiple is not a batch extrinsic

subtensor.add_stake_multiple() and subtensor.unstake_multiple() loop over their inputs and submit one extrinsic per hotkey. Each transaction is settled independently — they are not atomic. Use the Utility.batch_all pattern above when you need all-or-nothing semantics or want to pay a single transaction fee for the group.