---
title: "addCustomHeader(_:)"
framework: TelephonyMessagingKit
role: symbol
role_heading: Instance Method
platforms: [iOS 26.0+]
path: "telephonymessagingkit/mmspartcontent/addcustomheader(_:)"
---

# addCustomHeader(_:)

A helper function to add custom headers.

## Declaration

```swift
mutating func addCustomHeader(_ header: MMSPartContent.MMSCustomHeader)
```

## See Also

### Working with custom headers

- [customHeaders](telephonymessagingkit/mmspartcontent/customheaders.md)
- [MMSPartContent.MMSCustomHeader](telephonymessagingkit/mmspartcontent/mmscustomheader.md)