Cron Job Every Month

Cron expression for every month

0 0 1 * *

At 00:00, on day 1 of the month. It runs on 12 days a year.

Runs at midnight on the 1st of every month. @monthly is the same. Typical uses are invoices, monthly reports, rotating keys and archiving last month’s logs. Days 29–31 don’t exist in every month, which is why monthly jobs almost always use the 1st.

Field by field

Examples

crontab

Run crontab -e and add:

0 0 1 * * /usr/local/bin/job.sh >> /var/log/job.log 2>&1

Kubernetes CronJob

apiVersion: batch/v1
kind: CronJob
metadata:
  name: my-job
spec:
  schedule: "0 0 1 * *"
  timeZone: "Etc/UTC"          # Kubernetes 1.27+
  concurrencyPolicy: Forbid    # skip a run if the last one is still going
  jobTemplate:
    spec:
      template:
        spec:
          containers:
            - name: job
              image: ghcr.io/acme/job:1.0
          restartPolicy: OnFailure

GitHub Actions

on:
  schedule:
    - cron: '0 0 1 * *'   # UTC

GitHub evaluates schedules in UTC, and runs can start several minutes late at busy times.

systemd timer

# /etc/systemd/system/job.timer
[Unit]
Description=Run job.service every month

[Timer]
OnCalendar=*-*-01 00:00:00
Persistent=true

[Install]
WantedBy=timers.target

Enable it with systemctl enable --now job.timer, and check the next runs with systemd-analyze calendar "*-*-01 00:00:00". Persistent=true runs a missed job after downtime, which cron can’t do.

AWS EventBridge

cron(0 0 1 * ? *)

EventBridge cron has six fields (the last is the year), uses ? in either the day-of-month or the day-of-week field, and numbers weekdays from 1 (Sunday) to 7. Rules run in UTC; EventBridge Scheduler also accepts a time zone.

Similar schedules: monthly and yearly

• On the 15th of every month: 0 0 15 * *
• Twice a month: 0 0 1,15 * *
• On the last day of the month: 55 23 28-31 * *
• On the first Monday of the month: 0 9 1-7 * *
• Every quarter: 0 0 1 */3 *
• Every 6 months: 0 0 1 */6 *
• Every year: 0 0 1 1 *

Have a different schedule? Paste any expression into the Cron Expression Generator, or browse all cron examples.

Sources

• POSIX: crontab
• crontab(5) manual page
• Kubernetes docs: CronJob
• GitHub Actions docs: schedule event
• systemd.time(7): calendar events
• AWS docs: EventBridge Scheduler cron expressions

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Frequently asked questions