01 Bring two forms of ID for the I-9 Passport alone works; otherwise driver's license plus social security card or birth certificate. Don't show up without them — it delays everything. 02 Fill out your W-4 deliberately Don't autopilot. If your parents still claim you as a dependent, don't claim yourself. Review line 4c if you want extra withheld. 03 Fill out state withholding (if applicable) Separate form, often forgotten. If your state has income tax, you'll owe later if you skip this. 04 Set up direct deposit carefully Triple-check account and routing numbers. A typo sends your first paycheck to a stranger. 05 Enroll in health insurance within the window You usually have 30 days from hire date. Miss it and you wait until open enrollment (typically next fall) or a qualifying life event. 06 Compare health plans on total cost, not just premium Run the math for both low-deductible and high-deductible scenarios. 'Low premium' isn't the same as 'low total cost.' 07 Open an HSA if eligible Only available with a high-deductible plan. Triple tax advantage — contribute at least enough to capture any employer seed. After 65 it acts like an extra retirement account. 08 Enroll in 401(k) at least at the match maximum Whatever percentage gets you the full employer match. Below that is turning down free money. 09 Pick a target-date fund in your 401(k) Unless you know what you're doing, the 'target date X' fund near your expected retirement is the sensible default. 10 Check vesting schedule for the match Your contributions are always yours. Employer contributions may vest over years. Know the dates if you might leave early. 11 Turn on auto-escalation if offered Raises your 401(k) contribution by 1% a year automatically. Future-you will thank you. 12 Enroll in disability insurance if offered Short-term and long-term. Often cheap. Replaces income if you can't work. Most people don't think about it until they need it. 13 Opt into commuter benefits if you qualify Pre-tax dollars for public transit or parking. Free money if you use them. 14 Bookmark your payroll and benefits portals Often different vendors. You'll want paystubs, W-2s, 401(k) account, and health portal within easy reach. 15 Verify your first paystub line-by-line Check tax withholdings, health deductions, and 401(k) contribution all look right. Errors happen. 16 Roll over any old 401(k) If you had retirement accounts at previous jobs, roll them into your new 401(k) or a personal IRA. Don't leave them orphaned. 17 Ask your manager for 30/60/90 day expectations Ideally in writing. Sets you up for a real performance conversation later. 18 Save every onboarding doc to your personal drive Offer letter, benefits summary, vesting schedule. You'll want them later and you lose access to the work drive when you leave.