# Get Allowance

If source quoting asset is an ERC20 token, you should ensure that source token owner has approved sufficient token amount to spender before proceed swap operation. This endpoint provide convenient way to check ERC20 allowance amount.

{% openapi src="<https://3694085950-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-Mcs9EhDrgbKHodtcAT6%2Fuploads%2FnbSx9SgRqHu6Fj5VWo1E%2Fopenapi.json?alt=media&token=aa194fc4-5d6d-43c2-b4f2-e972276123f6>" path="/allowance" method="get" %}
[openapi.json](https://3694085950-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-Mcs9EhDrgbKHodtcAT6%2Fuploads%2FnbSx9SgRqHu6Fj5VWo1E%2Fopenapi.json?alt=media\&token=aa194fc4-5d6d-43c2-b4f2-e972276123f6)
{% endopenapi %}

{% hint style="info" %}
**NOTE :** The spender should be the `contractAddress` in the response of [Get Quote](https://docs.xy.finance/bridge-aggregator-integration/xy-finance-api-multiple-bridges-aggregator/get-quote).\
e.g. `routes[{ROUTE_INDEX}]["contractAddress"]`
{% endhint %}

{% hint style="info" %}
Here you can find our full [API reference](https://aggregator-api.xy.finance/v1/docs)
{% endhint %}