Picture this: an employee opens their pay stub expecting to see 3% of their salary going into their 401(k). Instead—nothing. Payroll missed the deferral months ago. By the time anyone notices, the company owes back contributions, lost earnings, and maybe even penalties.

The short answer: it depends.

The long answer: there are four main cost categories, and how you structure them determines whether you get a fair, sustainable plan—or one that frustrates employees and exposes your company to liability.

Think of a 401(k) like building a house—you’ll pay for the architect, the contractor, and the materials. Skip one, and the whole structure is at risk. The same is true for retirement plans.

Starting 1/1/2026, SECURE 2.0 requires Roth-only catch-up contributions for HCEs. Here’s exactly what’s changing, and the simplest way to avoid getting stuck. 

For HR leaders, payroll managers, and highly compensated employees trying to stay ahead of SECURE 2.0, one mistake is proving more costly than any other. 

What’s tripping people up right now isn’t the rule. It’s the delay in acting on it. 

Across the industry, we’ve seen this pattern again and again. Plans know the change is coming. But the assumption that “someone else is handling it” has quietly become the biggest threat to compliance. 

If you’re a business leader exploring a 401(k) for your employees, you probably have the same first question everyone else does: “How much is this going to cost us?”