Formal:
* "C'était agréable de discuter avec vous." (It was pleasant to chat with you.) This is the most formal option.
* "J'ai apprécié notre conversation." (I appreciated our conversation.) This is also quite formal, but slightly less so than the first option.
Informal:
* "C'était bien de parler avec toi." (It was good to talk with you.)
* "J'ai passé un bon moment à discuter avec toi." (I had a good time talking with you.)
* "On s'est bien entendus." (We got along well.) This is a more casual way of saying it.
Even more casual:
* "A bientôt !" (See you soon!)
* "Bonne journée !" (Have a good day!)
You can also use a more specific phrase depending on the topic of your conversation, like:
* "Merci pour vos conseils." (Thank you for your advice.)
* "J'ai beaucoup appris de vous." (I learned a lot from you.)
* "J'espère que vous passerez une bonne journée." (I hope you have a good day.)
The best option for you will depend on the specific situation.