Others

How to Import Work Hours and Resources from CSV into Microsoft Project

Muhammad Talha Oct 1, 2026 869 views

Question details

The user needs to reliably import work hours, scheduling data, and resources from a CSV file into Microsoft Project without unintentionally altering existing task dates, durations, or time-phased assignments.

How to Import Work Hours and Resources from CSV into Microsoft Project

Product: Microsoft Project
Device & OS: not provided
Scenario: Importing external scheduling and resource data (e.g., from Deltek Open Plan) into an existing Microsoft Project file via CSV.
Observed behavior: Importing the CSV data causes task dates, durations, and work to recalculate unexpectedly, and mapping resource IDs sometimes creates duplicate new resources instead of matching existing ones.

Before you start

Before importing your CSV file, ensure that your project's company calendar and start dates are properly configured, and make a backup copy of your Microsoft Project file to prevent unintended data loss during the mapping process.

Solution 1Recommended

Map Assignments and Verify Resource Identifiers

Ensure that tasks, resources, and assignments are correctly identified and mapped in the import wizard to prevent MS Project from creating duplicates or altering task durations.

When importing data that includes resources and assignments, Microsoft Project's scheduling engine can automatically recalculate tasks based on the new inputs. Carefully configuring the Import Map is essential for maintaining schedule integrity.

Launch the Import Wizard

Open Microsoft Project, go to 'File' > 'Open', browse for your computer, change the file type dropdown to 'CSV (Comma delimited)', and select your external data file to launch the Import Wizard.

Select the Merge Option

Progress through the wizard and choose the option to merge the data into the active project rather than creating a new project.

Review the Assignment Map

When prompted to map fields, carefully review the 'Assignment Map' and 'Task Map' tabs. Importing external information as task data is often more reliable than attempting to merge deep assignment data directly.

Map by Resource Name

If your external system provides resource names, map the external field to 'Resource Name' instead of 'Resource ID'. This helps Microsoft Project accurately match incoming data to existing resources.

Map Assignments and Verify Resource Identifiers

Resource Matching Limitations: Task views do not natively include a Resource ID field for mapping. Mapping by Resource Name often prevents the creation of unintended new resources when merging data.

Solution 2

Transform External Data in a Spreadsheet Before Importing

If direct CSV import causes scheduling shifts or mapping failures, use a spreadsheet program to clean and align the data with MS Project's structure first.

Free Microsoft Office alternative

Manage Project Data and CSVs Easily with WPS Office

While Microsoft Project is required for managing .mpp files, WPS Spreadsheet is an excellent, free alternative to Microsoft Excel for cleaning, transforming, and managing your CSV resource data before importing it into project management tools. It offers a lightweight, familiar interface to help you prepare your project data efficiently.

1. Download WPS Office: Download and install the free version of WPS Office on your device.
2. Open your CSV file: Launch WPS Spreadsheet and open your raw external CSV data file.
3. Edit and Prepare: Use WPS Spreadsheet's powerful editing tools to align resource names and clean task data, then save the CSV for a smooth import into your project software.

Fully compatible with Microsoft Excel formats (.xlsx, .csv, .xls)Easily clean and transform project resource data before importingLightweight software with a familiar, easy-to-use interfaceBuilt-in advanced formulas for data mapping and formatting

microsoft office alternative - wps office

Frequently Asked Questions

Why do my task dates change when I import a CSV into Microsoft Project?

This typically happens because importing time-phased assignments or resources triggers MS Project's auto-scheduling engine. For in-progress or Fixed Work tasks, the software recalculates start and finish dates based on the newly imported work hours and resource calendars.

Can I map Resource IDs instead of Resource Names during a CSV import?

MS Project's task views do not directly expose the internal Resource ID field for mapping in the Import Wizard. It is highly recommended to map using the Resource Name field to avoid creating duplicate resources.

How do I prevent new resources from being created when importing assignment data?

Ensure that the 'Resource Name' column in your CSV perfectly matches the exact spelling of the existing resources in your MS Project file. Verify this alignment in the Assignment Map step of the Import Wizard before completing the merge.

Does the project start date or company calendar affect CSV imports?

Yes. If your project has a specific start date and company calendar configured, importing external scheduling data that conflicts with these calendar constraints (such as work hours assigned on non-working days) will cause the software to adjust the task schedules automatically.

Office Quick Solutions