Hi Bob,
Thank you for your interest in Syncfusion Essential DocIO.
Yes, we do have the support for merging the data to the merge fields in the word document using Mailmerge feature in Essential DocIO. Please refer the following web sample that gets the data from Northwind database and merge the data to template document and streaming the output PDF and WORD documents to the client browser.
Sample :
Mail merge sample.zip
Also, you can find related samples in following url
C:\Program Files\Syncfusion\Essential Studio\4.3.0.30\Web\docio.web\Samples\2.0\Mailmerge
Please let me know if you have any other questions.
Regards,
Dhivya.