How to put desired umask with SFTP?

Since OpenSSH 5.4p1 I think, you can use the "-u" option, for example:

Subsystem sftp /usr/lib/openssh/sftp-server -u 022

From the man page:

 -u umask
         Sets an explicit umask(2) to be applied to newly-created files
         and directories, instead of the user's default mask.

I hope this can save someone else hours of frustration...

If you're using a GUI SFTP application, check its preferences for setting permissions on upload.

I had tried all the solutions above, and it turns out the application was just overriding them.

In the ssh config file you can also use this to set the mode of the file specifically (overriding any chmod that the client may try to set). Here I am using internal-sftp but I guess it would be the same for sftp-server:

ForceCommand internal-sftp -u 0022