Etiquette question

[fat old seagull]

Offer to pay it back. Any mild shock he feels (if any) at your offer should be outweighed by pleasure that he's met an honourable person who remembers his debts. If he declines, accept the gift with good grace.

In addition - do as @el punal suggests!

.....is the correct answer.
Unless he's a Nigel, then tell him you've spent the three quid on 3/4 of a pie at the Amex.

 

[Ⓩ-Ⓐ-Ⓜ-Ⓞ-Ⓡ-Ⓐ]

I'd ask for his home address and send round a hooker as a gesture of gratitude

 

[Hampster Gull]

He might accept a date!

 

[Vegas Seagull]

Forget it, he walked off as he doesn't want friends that don't carry enough cash to even buy a beer

 

[Nibble]

You can do that on social media?

PM'd.

 

[Munchkin]

Chris Eubank has written a book about ethics. If it's a success he's intending on doing follow up books on Kent and Lancashire.