---
title: "Field to constant mapping"
slug: "bc-field-to-constant-mapping"
tags: ["BC", "BIS", "Business Central", "Business Integration Solutions", "Concept", "Task"]
updated: 2026-06-25T09:59:07Z
published: 2026-06-25T09:59:07Z
canonical: "docs.staedean.com/bc-field-to-constant-mapping"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://docs.staedean.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Field to constant mapping

With field-to-constant mapping, you can specify fixed values for fields in a target document.

## Usage

Use field-to-constant mapping to add a fixed value to the target document. This type of mapping also applies when the source document does not contain a required field in the target document. For example, you can map the **Type** field in the **Sales Line** table to a constant value such as Item.

## Concept

You must configure a source document and a target document to set up a mapping activity. On the **Mapping Activity Lines** page, you can specify a fixed value for each target document field. After mapping, the target field always contains a constant value.

Use the Expression Wizard to specify a fixed value, or enter a fixed value directly on the **Mapping Activity Lines** page.

> [!NOTE]
> **Note**
> 
> Always enclose a constant value in double quotes, as shown in the following example.

```plaintext
"Constant Value"
```

In the example below, the DocumentType node maps to a constant value.

![Example of Mapping](https://cdn.document360.io/da662430-6a41-47b1-8c7e-7e4ac37a9756/Images/Documentation/MappingWithExpression.png)

## Related

- [Mapping](/bc-bis-mapping.md)