# after_transfer · FT4 Rell API · Chromia Docs (concept)

> @extendable function after_ transfer(from: account , to: account , asset: asset , amount: big_ integer) Extendable function that allows the developer to ad

Source: https://docs.chromia.com/pages/ft4-rell/-f-t4-library/lib.ft4.core.assets/after_transfer/

FUNCTION

# after\_transfer

```signature
@extendable function after_transfer(from: account, to: account, asset: asset, amount: big_integer)
```

[Source](https://gitlab.com/chromaway/ft4-lib/-/blob/development/rell/src/lib/ft4/core/assets/extensions.rell#lines-36)

Extendable function that allows the developer to add more functionality to the
`transfer` function, after the transfer happens.

This allows, for example, to add fees on transfer or check that any given condition
is present after the transfer is completed.

If this function throws an exception, the assets will not be transferred.

Throws if any extension of this function throws.

**Parameters**

* **from** — the account that started the transfer
* **to** — the account that should receive the transfer
* **asset** — the asset that should be sent
* **amount** — the amount to transfer

[View this page on docs.chromia.com](https://docs.chromia.com/pages/ft4-rell/-f-t4%20-library/lib.ft4.core.assets/after_transfer.html)Generated API reference, mirrored from the live docs