How to Filter a CSV by Date (Keep Rows Before, After or Between Dates)

To filter a CSV by date, pick the date column, choose before, on or after, or between, and type the cut-off dates. The filter CSV rows by date tool reads mixed date styles, shows how many rows are kept and gives you the rows kept and the other rows as separate files. Rows with a blank or unreadable date are set apart, not guessed.

Old addresses go bad as people change jobs and abandon inboxes, so a date cut is a common first step in list hygiene.

Why filter by date

A list sorted by sign-up date shows which part is oldest, so you can check or retire it first. A filter for after a date keeps the recent signups. A range keeps one campaign's signups or one month's imports. For when to stop mailing the oldest contacts, read how to write a sunset policy.

Step 1: do it by hand

In Excel, apply a filter to the header, open the date column's dropdown and choose Date Filters. This works only if the cells are real dates. A CSV opened in Excel often leaves dates as text, especially when they come in mixed styles, and then the Date Filters option does not appear. Text dates have to be converted first.

Step 2: use the tool

1. Upload the CSV or .xlsx, or paste the cells with the header row first.
2. Pick the date column and choose before, on or after, or between.
3. Choose the date or dates, and the day and month order if the list is mixed.
4. Check the counts and download the rows kept and the other rows.

The tool reads 2026-03-14, 14/03/2026, 03/14/2026, 14.3.2026, 14 Mar 2026, March 14th 2026 and Mar 14, 2026. A time after the date is ignored and a two-digit year is read as 20yy. The cut-off day is included in on or after and in between, and excluded from before, so before 2026-01-01 keeps 31 December 2025 and earlier.

The 03/04/2026 problem

A date such as 03/04/2026 is 3 April in most of the world and 4 March in the United States. If any date in the column has a first number above 12 or a second above 12, the order is worked out for the whole column. If not, month first is assumed and you are told, and you can choose the order yourself. For more on this, see CSV dates and the day and month order. To rewrite the whole column into one style first, use the CSV date format converter.

Rows with no date

A blank cell, or a date that cannot be read, is counted and downloaded with the rows outside the range. Nothing is dropped silently. Dates with only a month and a year, or written in another language, are not read and are set apart.

What this cannot do

• It does not read the clock, so you type the cut-off.
• An all-number date with both parts 12 or below can be ambiguous; the order is assumed or chosen.
• Only the first sheet of a workbook is read.
• A date says when a row was added, not whether the mailbox still works.

To find contacts who stopped engaging, use the inactive subscriber finder.

Verify the old rows before you mail them

Age is a reason to check, not proof an address is dead. Upload the list on the verify page: the first 100 email checks are free with a Google sign-in, no card. Each address comes back valid, risky or invalid with a reason, and nothing is sent to anyone on the list. For larger or recurring lists, see bulk email verification, list cleaning and pricing.

Filter your list now

Upload the file to filter CSV rows by date.