Your Server's Memory as the Limit
When uploading locations in bulk, the only limit is how much memory you have on your server.
Uploading Locations in Batches
We recommend using batches of 1000 per 128MB in your php.ini config file. For example, if you have it set to 256MB, you can batch upload 2000 entries at a time. So if you have 10,000 locations, you should have 5 separate batch upload files.