Formal:

Goodbye

Have a good day

Farewell

So long

It was nice meeting you (when you meet someone for the first time)

Neutral:

Bye

See you next time

See you soon

Until next time

Take care

It was nice talking to you

It was nice seeing you (usually to someone of the opposite gender or a family member that you haven't seen for a long time, or to a group of people)

Informal:

Bye

See you/ya/ye later

Have a good one

'til later

Later

If you're talking to someone who you don't know that was helping you (like a shopkeeper), you can just say 'thanks'.

If someone says "see you later later/soon/tomorrow/Monday... etc.", you can respond "see you then" or "until/'til then".

Good bye

Take Care

See you

So long

Working in the hospitality business for years, I definetly use "Have a good day/night" most often in a formal way.

Formal:

Best Regards,

Your's Trully,

Yours Sincerely.

Informal :

Good Bye,

See you Soon,

Its Pleasure to be with you-take care,

Have a nice day,

Ways to say Goodbye:

<em>Farewell</em>

<em>Have a good day</em>

<em></em><em>Have a good one</em>

<em>Catch you later</em>