> For the complete documentation index, see [llms.txt](https://help.smallbuilder.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.smallbuilder.com/smallbuilder-line-items/builder/builder-setup-steps/setup-line-item-editor/set-field-input-as-required.md).
# Set Field Input as Required
Designate a Line Item field input as required to ensure users provide the necessary information.
### Example: Setting a Field as Required
Fields designated as required are marked with a red line on the left side of the input box.
If a required field value is not entered before saving, an error message will be displayed as shown below.
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