Run a Job on December 31st at 5:29 AM

cron expression Standard

$ 29 5 31 12 *

→

On December 31st, at 5:29 AM, once a year.

Minute

Hour

Day of Month

Month

Day of Week

* In a Nutshell

The cron expression 29 5 31 12 * runs On December 31st, at 5:29 AM, once a year.. This annual cadence is crucial for tasks that must execute precisely once per year, such as year-end financial closing, regulatory reporting deadlines, or archiving processes that depend on complete annual data. Executing on a specific date like New Year's Eve ensures that all preceding year's data is finalized before the task runs, preventing data gaps for critical annual summaries.

* When to use this

Use 29 5 31 12 * when a recurring task needs to run On December 31st, at 5:29 AM, once a year.. This schedule is commonly associated with financial processing and monthly schedules and report generation workloads. It uses Standard (5-Field POSIX) syntax, supported by Unix cron daemons, cloud schedulers such as AWS EventBridge, and container orchestration platforms such as Kubernetes CronJob.

CronBase parses 29 5 31 12 * using a dialect-aware rules engine that identifies the Standard (5-Field POSIX) format, validates field structure against the Standard (5-Field POSIX) specification, and produces the translation above. Next run times are calculated by forward-scanning from the current UTC clock. Learn how CronBase works.

Platform Implementations

Bash

Prerequisites

Unix/Linux host with a cron daemon running (vixie-cron, cronie, or systemd-cron). The script at /usr/local/bin/run-task.sh must exist and be executable (chmod +x).

Configuration

Run crontab -e to open the crontab editor. Cron reads the server's local timezone; prefix with CRON_TZ=UTC before the expression to pin to UTC. Always redirect output with >> /var/log/cron-tasks.log 2>&1 to capture both stdout and stderr.

Gotchas

Cron jobs inherit a minimal PATH — use full binary paths or set PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin at the top of the crontab. For sub-hourly schedules, add flock -n /tmp/run-task.lock before the command to skip overlapping runs if the previous execution is still running.

bash

# Add to crontab with: crontab -e
29 5 31 12 * /usr/local/bin/run-task.sh >> /var/log/cron-tasks.log 2>&1

Last verified: May 29, 2026

Nodejs

Prerequisites

Node.js 18+ with node-cron installed (npm install node-cron). Add "type": "module" to package.json to use the import syntax shown above.

Configuration

Pass { timezone: 'UTC' } as the third argument to cron.schedule(). Without this option the schedule uses the Node.js process timezone, which shifts during DST transitions when servers are not pinned to UTC.

Gotchas

node-cron uses standard 5-field cron syntax — not Quartz 6-field. If your job runs longer than the schedule interval the next trigger fires while the previous is still executing. Use a boolean guard or a queue to skip concurrent runs rather than relying on the scheduler to enforce it.

nodejs

import cron from 'node-cron';

cron.schedule('29 5 31 12 *', async () => {
  console.log('[cron] running at', new Date().toISOString());
  // your task logic here
}, { timezone: 'UTC' });

Last verified: May 29, 2026

Python

Prerequisites

Python 3.8+ with apscheduler installed (pip install apscheduler). For Python 3.12+ use apscheduler>=3.10.

Configuration

CronTrigger.from_crontab() accepts a standard 5-field cron string. Always pass timezone='UTC' to both the BlockingScheduler constructor and the trigger to ensure consistent scheduling regardless of the server's locale.

Gotchas

BlockingScheduler.start() blocks the calling thread indefinitely. For a web application, use BackgroundScheduler instead and call scheduler.start() at application startup. APScheduler logs missed fires if the process is stopped and restarted — configure misfire_grace_time (in seconds) to control how late a missed job is allowed to run.

python

from apscheduler.schedulers.blocking import BlockingScheduler
from apscheduler.triggers.cron import CronTrigger

scheduler = BlockingScheduler(timezone='UTC')

@scheduler.scheduled_job(
    CronTrigger.from_crontab('29 5 31 12 *', timezone='UTC')
)
def run_task() -> None:
    print('task running')
    # your task logic here

scheduler.start()

Last verified: May 29, 2026

Golang

Prerequisites

Go 1.18+ and github.com/robfig/cron/v3 (go get github.com/robfig/cron/v3).

Configuration

Always create the scheduler with cron.New(cron.WithLocation(time.UTC)). Without WithLocation, the library defaults to the server's local timezone. Call c.Start() to begin the scheduler, then block with select {} to keep the process alive.

Gotchas

robfig/cron v3 uses standard 5-field cron expressions by default. To add second-level precision (6 fields), pass cron.WithSeconds() to cron.New() — but this changes field positions, so never mix syntaxes in the same scheduler. Always check the error returned by c.AddFunc() — a malformed expression is silently ignored without it.

golang

package main

import (
	"fmt"
	"time"

	"github.com/robfig/cron/v3"
)

func main() {
	c := cron.New(cron.WithLocation(time.UTC))
	_, err := c.AddFunc("29 5 31 12 *", func() {
		fmt.Println("task running at", time.Now().UTC())
		// your task logic here
	})
	if err != nil {
		panic(err)
	}
	c.Start()
	defer c.Stop()
	select {}
}

Last verified: May 29, 2026

Java

Prerequisites

Spring Boot 2.7+ (or Spring Framework 5.3+) with spring-context on the classpath. Annotate your @SpringBootApplication class with @EnableScheduling — without it, @Scheduled methods are silently ignored.

Configuration

Spring @Scheduled uses a 6-field Quartz-style expression: [sec] [min] [hr] [dom] [mon] [dow]. The expression 0 29 5 31 12 ? is derived from 29 5 31 12 * — a leading 0 is prepended for the seconds field, and ? replaces the unconstrained day field.

Gotchas

Standard Unix cron has 5 fields; Spring requires 6. Pasting a 5-field expression directly into @Scheduled shifts every field by one and the job misfires silently. Use ? for either dom or dow — Quartz does not allow both to be *.

java

import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Component;

@Component
public class ScheduledTask {

    @Scheduled(cron = "0 29 5 31 12 ?")
    public void runTask() {
        System.out.println("task running at: " + java.time.Instant.now());
        // your task logic here
    }
}

Last verified: May 29, 2026

Kubernetes

Prerequisites

Kubernetes 1.21+ (CronJob API is GA). kubectl configured with cluster access. Container image must be pullable from within the cluster.

Configuration

Apply with kubectl apply -f cronjob.yaml. Check status with kubectl get cronjobs and inspect run history with kubectl get jobs. concurrencyPolicy: Allow is set because this schedule fires infrequently — parallel runs are acceptable.

Gotchas

Without startingDeadlineSeconds, a missed job (e.g., due to cluster downtime) triggers as soon as the controller recovers. Kubernetes 1.25+ supports timeZone: UTC in the spec to avoid timezone ambiguity. Keep successfulJobsHistoryLimit and failedJobsHistoryLimit low to avoid accumulating stale Job objects in the cluster.

kubernetes

apiVersion: batch/v1
kind: CronJob
metadata:
  name: scheduled-task
spec:
  schedule: "29 5 31 12 *"
  concurrencyPolicy: Allow
  jobTemplate:
    spec:
      template:
        spec:
          restartPolicy: OnFailure
          containers:
          - name: task
            image: alpine:3.19
            command: ["/bin/sh", "-c", "echo 'task running'"]

Last verified: May 29, 2026

AWS EventBridge Equivalent

Standard cron expressions often need conversion for AWS EventBridge schedules.

EventBridge Rule

cron(29 5 31 12 ? *)

Frequently Asked Questions

What specific task does the 29 5 31 12 * cron expression trigger?

This cron expression is configured to trigger a specific task exactly once per year, on December 31st at 5:29 AM. It's ideal for tasks that must run at the end of the calendar year after all annual data is available and finalized.

How does this schedule handle Daylight Saving Time or clock changes?

Since this schedule runs only once a year on a fixed date and time, any clock adjustments due to Daylight Saving Time changes will not cause it to run twice or be skipped. The system will execute it at the local time specified.

How can I verify that my job ran successfully on December 31st?

To verify successful execution, check the job's logs immediately after the scheduled run time on December 31st. Look for successful completion messages or any error reports generated by the task itself.

Are there any potential issues with running a job at this specific time?

A key consideration is that this runs on December 31st, which is often a public holiday and systems may be under different load conditions or have reduced monitoring staff. Ensure the task is robust enough to run unattended or schedule it for a time with minimal system impact.

What is a common variation or alternative to this annual schedule?

A common variation might be to run a similar task on January 1st at midnight, effectively capturing the very beginning of the new year for processing. This ensures all data from the prior year is definitely complete before execution.