Delta companion ticket, can I upgrade it with cash?

[schoen]

Hi! I am getting ready to book airfare. We have a companion ticket to use with our Delta card. We want to use it for a main cabin ticket, but can I then pay the fare difference to upgrade that seat to 1st class?
thanks!

 

[spiders]

If you’re asking if you can do it on the initial booking then I don’t think you can. If you’re asking if you can do a paid upgrade after booking then the answer is yes.

 

[EACarlson]

This is with the Delta Amex Platinum? You would need to book the ticket into MC, then you should be able to do an upgrade in the app or on the site. There are some other benefits you may not get since it's not a paid FC ticket.