Pensions and retirement saving in the United States
Reviewed by Mellow Editorial Team, HR & payroll content team
Retirement saving in the United States is largely voluntary and employer-facilitated, with no universal mandatory workplace pension. What you save — and how — depends on the plans your employer offers, your own contributions, and the tax treatment of each account type.
The basics: no mandatory workplace pension
Unlike many countries, the US has no statutory requirement for employers to enroll workers in a pension scheme or contribute on their behalf. Social Security provides a baseline retirement benefit funded through FICA payroll taxes — employees contribute 6.2% of wages toward Social Security up to the annual wage base, and employers match that amount — but Social Security alone is rarely enough to maintain someone's pre-retirement standard of living. Most financial planners treat it as a floor, not a plan.
Beyond Social Security, retirement saving is built around employer-sponsored plans and individual accounts, both governed by tax rules set by the IRS.
401(k) plans: the most common employer-sponsored option
A 401(k) is a defined-contribution plan offered through an employer. Employees elect to defer a portion of their paycheck into the plan, and those contributions reduce their current taxable income. Investment growth is tax-deferred, meaning taxes are owed only when money is withdrawn in retirement.
Key features:
- Employee contributions come out of pre-tax wages, lowering the employee's federal (and usually state) income tax bill for the year.
- Employer matching is common but not required. A typical match might be 50% or 100% of employee contributions up to a set percentage of salary. This is effectively additional compensation — employees who don't contribute enough to capture the full match leave money on the table.
- Vesting schedules govern when employer contributions become fully the employee's property. Some plans vest immediately; others use a graded or cliff schedule over several years.
- Investment choices are managed by the employee from a menu of funds selected by the plan.
- Early withdrawal before age 59½ generally triggers income tax plus a 10% penalty, with limited exceptions.
Roth 401(k) versions also exist. Contributions go in after tax, but qualified withdrawals in retirement are tax-free — useful if an employee expects to be in a higher tax bracket later.
IRAs: individual retirement accounts
Employees can also save independently through Individual Retirement Accounts. Two main types:
- Traditional IRA — contributions may be tax-deductible depending on income and whether you have a workplace plan. Growth is tax-deferred.
- Roth IRA — contributions are made with after-tax dollars, but qualified withdrawals are tax-free. Eligibility phases out at higher income levels.
IRAs have annual contribution limits set by the IRS that are lower than 401(k) limits, and catch-up contributions are allowed for workers aged 50 and over. These accounts are held individually and are portable regardless of employer.
Other plan types worth knowing
Not every employer offers a 401(k). Smaller businesses and nonprofits sometimes use alternatives:
- SIMPLE IRA — designed for small employers. Requires employer contributions, either a match or a flat percentage of all eligible employees' compensation.
- SEP-IRA — primarily used by self-employed individuals and small business owners. Allows relatively high contribution limits funded entirely by the employer.
- 403(b) — functionally similar to a 401(k) but offered by public schools, universities, hospitals, and other nonprofits.
- Defined benefit (pension) plans — traditional pensions that promise a specific monthly benefit at retirement. These are now rare in the private sector but still common in some government and union environments.
What employers need to understand
If you offer a 401(k) or similar plan, you take on responsibilities beyond simply setting it up. ERISA (the Employee Retirement Income Security Act) governs private-sector plans and imposes fiduciary duties — meaning you must act in participants' best interests when selecting and monitoring investment options and plan administrators.
Practical obligations include:
- Filing annual Form 5500 reports with the Department of Labor (plans above a certain size must have an independent audit).
- Providing a Summary Plan Description to all eligible employees.
- Running non-discrimination tests to ensure the plan doesn't disproportionately benefit highly compensated employees.
- Depositing employee contributions into the plan promptly — the DOL takes delays seriously.
For companies running payroll across multiple states, contribution rules and state tax treatment can add complexity. Some states with no income tax, such as Texas, Florida, and Washington, simplify the picture for employees but you still have full federal compliance obligations regardless of where workers are based. If you're managing a distributed workforce, understanding how payroll integrates with benefit deductions matters — how Mellow runs payroll across six countries covers some of that coordination in practice.
Choosing not to offer a retirement plan is legal for most private employers, but it increasingly affects hiring. Workers compare total compensation packages, and a missing 401(k) match is a visible gap.
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