What happens if a client only pays part of an invoice?

Kliently supports partial payments. If a client pays part of an invoice, that amount is reconciled against it and the remaining balance stays visible as still owed — so the invoice isn't falsely marked paid, and it isn't treated as fully unpaid either.

This is common with larger projects and staged work: a client clears half now, half on delivery. Both payments attach to the same invoice, the running balance is always correct, and reminders keep tracking against what's left until the full amount is in.