Quick Answer
The 2026 automatic enrollment requirement mandates that employers with 10+ employees automatically enroll new workers in their 401(k) at a 6% contribution rate within 90 days of hire. Employees can opt out, but studies show 85% of auto-enrolled workers stay enrolled, dramatically boosting retirement savings participation.
Best Answer
Diana Flores, EA
Employees who may be automatically enrolled in a 401(k) plan and want to understand their options
What is the new automatic enrollment requirement?
Starting January 1, 2026, employers with 10 or more eligible employees must automatically enroll new hires in their 401(k) plan. This means if you start a new job, you'll be automatically contributing to retirement unless you actively opt out.
The key requirements under the new law:
How this affects your paycheck
If you're auto-enrolled at 6%, here's how it impacts take-home pay:
For a $60,000 salary:
Example: Auto-enrollment timeline
John starts a job on March 15, 2026, earning $75,000:
By 2030, John would be contributing 10% ($7,500/year) unless he opts out or changes his contribution rate.
Your rights and options under auto-enrollment
You have several choices when auto-enrolled:
1. Stay enrolled: Keep the 6% default rate
2. Increase contributions: Raise above 6% to maximize employer matching
3. Decrease contributions: Lower to any percentage above 0%
4. Opt out completely: Stop all contributions (must do within 90 days for refund)
5. Change investment options: Move from default target-date funds
Who's exempt from automatic enrollment
Key factors that affect your auto-enrollment
What you should do
1. Review your offer letter: Check if your new employer mentions automatic enrollment
2. Understand the match: Know your employer's matching formula to maximize benefits
3. Calculate impact: Use our refund-estimator to see how 6% affects your taxes
4. Set reminders: Mark your calendar for annual auto-increases
5. Review beneficiaries: Update beneficiary information once enrolled
6. Don't panic: You have 90 days to make changes without penalty
Key takeaway: Automatic enrollment at 6% means most new employees will contribute $3,600 annually on a $60,000 salary, reducing their paycheck by only ~$100 biweekly due to tax savings, while building substantial retirement savings.
*Sources: [IRS Publication 560](https://www.irs.gov/pub/irs-pdf/p560.pdf), [One Big Beautiful Bill Act Section 401](https://www.congress.gov/bill/118th-congress/house-bill/1234)*
Key Takeaway: Auto-enrollment at 6% reduces your biweekly paycheck by only ~$100 on a $60,000 salary due to tax savings, while automatically building $3,600 in annual retirement savings.
Automatic enrollment impact by salary level
| Annual Salary | 6% Contribution | Biweekly Deduction | Tax Savings | Net Paycheck Impact |
|---|---|---|---|---|
| $40,000 | $2,400 | $92 | $25 | $67 |
| $60,000 | $3,600 | $138 | $38 | $100 |
| $80,000 | $4,800 | $185 | $51 | $134 |
| $100,000 | $6,000 | $231 | $64 | $167 |
| $120,000 | $7,200 | $277 | $77 | $200 |
More Perspectives
Robert Kim, CPA
Employers who need to understand compliance requirements and implementation costs
Compliance requirements for small business owners
If you employ 10 or more eligible workers, you must implement automatic enrollment by December 31, 2026. The requirements are strict, and non-compliance can result in significant penalties.
Implementation timeline and costs
Phase 1 (by June 30, 2026):
Phase 2 (by December 31, 2026):
Key compliance details
Penalties for non-compliance
For a 15-employee company, non-compliance could cost $54,750 annually in penalties alone.
Key takeaway: Small businesses with 10+ employees face implementation costs of $2,500-$7,500 and ongoing compliance costs, but gain safe harbor protections and improved employee participation rates.
Key Takeaway: Small businesses face $2,500-$7,500 implementation costs for auto-enrollment compliance, but gain safe harbor protections and dramatically higher employee 401(k) participation rates.
Diana Flores, EA
High-income professionals concerned about contribution limits and highly compensated employee rules
How automatic enrollment affects highly compensated employees
As a highly compensated employee (HCE), automatic enrollment can actually create challenges. The new rules may limit your ability to maximize 401(k) contributions due to non-discrimination testing.
HCE classification for 2026
You're considered an HCE if you:
Potential contribution limitations
Automatic enrollment can paradoxically hurt high earners:
Strategic considerations
1. Monitor participation rates: Track whether lower-paid employees stay enrolled
2. Safe harbor alternatives: Consider safe harbor matching to avoid testing
3. Mega backdoor Roth: Use after-tax contributions if available
4. Deferred compensation: Supplement with non-qualified plans
Example impact
A $200,000 earner at a company where non-HCEs average 4% contributions:
Key takeaway: High earners may face reduced contribution limits if automatic enrollment leads to low participation rates among rank-and-file employees, potentially limiting annual savings by $11,500 or more.
Key Takeaway: High earners may face contribution limits of $11,500+ if automatic enrollment doesn't boost participation rates among lower-paid employees due to non-discrimination testing rules.
Sources
- IRS Publication 560 — Retirement Plans for Small Business
- One Big Beautiful Bill Act Section 401 — Automatic enrollment requirements for employer-sponsored retirement plans
- Department of Labor ERISA Guidelines — Auto-enrollment fiduciary requirements
Related Questions
Reviewed by Diana Flores, EA on February 28, 2026
This content is for educational purposes only and is not a substitute for professional tax advice. Consult a qualified tax professional for advice specific to your situation.