Polkadot Account Reaped: Existential Deposit and Lost Dust

On Polkadot an account exists only while its balance stays at or above the existential deposit (ED). If a transfer leaves less than that, the chain removes the account — it is 'reaped' — and the leftover dust below the ED is removed with it. That is the usual reason a few hundredths of a DOT seem to disappear after sending 'everything'. The same rule explains a failed transfer to a fresh address: if the amount is below the ED, the new account cannot be created and the transfer is rejected.

How large the existential deposit is

The ED is a runtime constant that differs per chain. On the Polkadot relay chain it is 1 DOT. System parachains such as Polkadot Asset Hub use one tenth of that, 0.1 DOT. Since DOT balances and everyday transfers have moved to Asset Hub — the network KOT.CASH's liquidity provider uses for DOT deposits and payouts — the 0.1 DOT figure is the one most users meet today. Values can change with runtime upgrades, so the Polkadot Wiki is the place to check before relying on a number.

Kusama and other parachains have their own values, and tokens on Asset Hub (USDT, USDC) have their own minimum balances set per asset.

Two transfer modes and why one is safer

Polkadot wallets offer two ways to send. Transfer keep-alive refuses any transfer that would bring your balance below the ED, protecting the account. Transfer allow-death (the old plain transfer) lets the account fall below the ED and be reaped. Polkadot.js shows a 'keep-alive' toggle; Nova, Talisman and SubWallet keep the account alive by default and warn when you choose to send everything.

• Sending your whole balance with allow-death: the account is removed, the transaction fee is paid, the dust is lost, the nonce resets.
• Sending to a new address less than the ED: the transfer fails, nothing moves except the fee.
• Locked or reserved funds (staking, identity, proxies) are not spendable and do not count towards keeping the account alive in the way the free balance does.

What 'reaped' looks like on Subscan

On Subscan the extrinsic shows Success, and the events list includes balances.Transfer, followed by balances.DustLost and system.KilledAccount for the sending account. The DustLost event shows the amount that vanished. If you search the account afterwards, Subscan may say it has no balance or show it as reaped. The guide to Subscan explains the event list in detail.

Why Polkadot works this way

Every account is a storage item that every node keeps forever unless it is removed. Without a minimum, anyone could create millions of accounts holding a single planck (the smallest unit, 10^-10 DOT) and bloat the state for free. The existential deposit makes each account cost a real amount to keep and gives the chain a clean way to delete abandoned ones. Ethereum has no such rule, which is one reason its state keeps growing; Cardano, Stellar and the XRP Ledger solve the same problem with their own minimums.

Common error messages

Practical rules

1. Keep at least the ED plus a margin for fees on every account you plan to keep — 0.2 DOT on Asset Hub is a comfortable floor.
2. When sending to someone's new address, send more than the ED; exchanges set withdrawal minimums above it for this reason.
3. Before closing an account deliberately, unlock staking and remove identity or proxies so the full balance is free, then send everything with allow-death.
4. Check which chain you are on: an amount above 0.1 DOT can still fail on the relay chain, where the ED is 1 DOT.

DOT deposits to a swap

When you pay a KOT.CASH order in DOT, send it on Asset Hub — the network shown on the order page — and keep enough DOT behind in your wallet to stay above the ED, or deliberately empty the account. The provider waits for 15 confirmations before crediting, typically well under two minutes. When you receive DOT, make sure the payout is above the ED of a new address, otherwise it cannot be delivered; the deposit confirmations table lists the current requirement.