The default endpoint for the Amazon S3 web service is
s3.amazonaws.com. It will work in most of the cases except when the bucket is region-specific.
If a created bucket is limited to only a specific AWS region, you might need to enter that region's specific endpoint when configuring the S3 Connection. The actual region-specific endpoint is:
s3-region.amazonaws.com, for example, as
Read about available AWS regions.