My bottom line is...

Meaning

My final, non-negotiable offer is...

Examples

• John: So, what's your best price?
• Alice: <b>My bottom line is</b> $500. I can't go any lower.
• John: Hmm, that's a bit high for me. Let me see what I can do.
• Alice: Okay, but <b>my bottom line is</b> still $500. This is my absolute lowest offer.