Sharepoint 365 - How to provide access to a service account?

Hi folks, 

my organisation has recently upgraded their Sharepoint to 365. Previous versions of Sharepoint had the facility to grant access to a service account (EMEA\xxx...), however it appears 365 can only grant access to users via an email address. Is this correct? If not, please can you let me know how I can provide access to the service account? 

Thanks very much in advance for any help you can offer

Regards,

David