We get a lot of these questions - it feels like the data should be free, right?
Anyway - here's a couple of links to places you can do batches of geocoding for free:
I use this one a lot: http://www.gpsvisualizer.com/geocoder/
And here's a long list of available services: https://webgis.usc.edu/Services/Geocode/About/GeocoderList.aspx
This link was tremendously helpful! literally cut and paste 500+ postal code and boom a fresh csv to import
You just saved me quite a lot of grief