Donorfy has a File Uploader that enables you to import data from Excel. You can download a Data Preparation Template from within your Donorfy system: Data Management > File Upload

Note: If you have made any alterations to the settings within Donorfy, click the Update Template button before you download the Data Preparation Template. The template includes your tag structure, which is why it's a good idea to sort that out before importing data!

You can find out how to import data here, and specific articles here, but it's worth repeating the golden rules:

1. Import Constituents first, with the contact ID (if you have one) in the external key.
2. then import Donations and Activities if you have them, using the external key (contact ID from your old system) to link them to the right constituents
3. upload Excel workbooks with one worksheet, not multiple.
4. don't change the tab names from the ones provided in the template
5. don't reformat the data in the template - paste Values (using Paste Special)
6. remove password protection or the upload will fail as it won't be able to access the data

Data import/migration is one area where the assistance of a partner is strongly recommended.