the end of this month; around the last days of the current month
今月末までにレポートを提出してください。
Please submit the report by the end of this month.
旅行は今月末に行く予定だ。
I'm planning to travel at the end of this month.
今月末は給料日だから、銀行が混むだろう。
Since payday is at the end of this month, the banks will probably be crowded.