---
title: copy_once mode
description: "The `copy_once` mode copies the source value without translation and only fills empty target values. ## At save time - Copies source value without translation. - Writes only into empty target values. ## During import - Copies source value to…"
url: "https://www.wp-polyfields.com/docs/field-translation-modes/copy_once-mode/"
updated: "2026-07-05"
category: Field Translation Modes
---

# copy_once mode

The `copy_once` mode copies the source value without translation and only fills empty target values.

## At save time

- Copies source value without translation.
- Writes only into empty target values.

## During import

- Copies source value to the default-language store only when the default-language value is empty.
- Propagates immediately to targets if the target value is empty.

## When to use

Use `copy_once` when each language needs an initial seed value but should then diverge. Ideal for media, relationships, and structural data such as hero images, linked CTA pages, and repeater or flexible layout structure. See [Field translation overview](https://www.wp-polyfields.com/docs/field-translation-modes/field-translation-overview/) for more guidance.