# Nylas domain certificates

Source: https://developer.nylas.com/docs/dev-guide/platform/nylas-domain-certificates/

Most of Nylas' domains are compliant with the [Let's Encrypt chain of trust](https://letsencrypt.org/certificates/). Some devices might receive errors if they access Nylas domains because they can't access websites secured by Let's Encrypt certificates.

The following Nylas domains use Let's Encrypt certificates:

- [`nyl.as`](/docs/dev-guide/platform/what-is-nyl/)
- `nylas.com`
- `nylas.team`
- `us.nylas.com`