---
title: "IRAs Now Hold More Than 401(k)s — but Rolled-Over Cash Often Sits Idle"
description: "Individual retirement accounts have quietly become the biggest pool of US retirement money — bigger than 401(k)s — mostly because workers roll old 401(k)s into them when they change jobs. The catch: that rolled-over money often lands in cash and just sits there, uninvested, for years."
category: "Personal Finance"
category_url: https://boursel.com/category/personal-finance
author: "Sofia Marchetti"
published: 2026-06-28T14:43:40.000Z
updated: 2026-06-28T14:43:40.000Z
canonical: https://boursel.com/article/iras-now-hold-more-than-401ks-but-rolled-over-cash-often-sits-idle
tags: ["retirement", "ira", "401k", "rollovers", "investing"]
---
# IRAs Now Hold More Than 401(k)s — but Rolled-Over Cash Often Sits Idle

Individual retirement accounts have quietly become the biggest pool of US retirement money — bigger than 401(k)s — mostly because workers roll old 401(k)s into them when they change jobs. The catch: that rolled-over money often lands in cash and just sits there, uninvested, for years.

This is general education, not investment advice. The figures use the US system; many countries have equivalent accounts.

## The quiet flip

**Individual retirement accounts (IRAs)** now hold roughly **$19 trillion**, well ahead of the **about $10 trillion** in 401(k) plans, [according to the Investment Company Institute](https://www.ici.org/research/stats/retirement), the fund industry's data body. That's a notable reversal: IRAs are now the single largest store of US retirement savings. And it isn't because people love IRAs — it's because of what happens when they leave a job. A large share of IRA money arrives as a **rollover** from a former employer's 401(k), and the ICI finds a majority of traditional-IRA households hold such rolled-over money.

## IRA vs. 401(k), in plain terms

A **401(k)** is a retirement plan your employer sets up: you contribute from your paycheck (often with a company match), and the employer picks the menu of investments. An **IRA** is one you open yourself at a brokerage like Vanguard, Fidelity or Schwab — you control it, and you choose what it's invested in (or whether it's invested at all). Each comes in two tax flavors: **traditional** (you get a tax break now, pay tax on withdrawals later) and **Roth** (you pay tax now, withdrawals are tax-free later).

## The trap: money that never gets invested

Here's the problem the data keep surfacing. When you roll a 401(k) into an IRA, your old plan usually **sells your investments and sends the money as cash**. It then sits in a cash or money-market position inside the IRA — earning very little — until you take a second step and actually buy investments. Many people never take that step, or forget the account exists.

Vanguard's research found that [a large majority of savers who left rollover money in cash didn't even realize it was sitting uninvested](https://corporate.vanguard.com/content/corporatesite/us/en/corp/articles/out-sight-out-market-ira-cash-drag.html) — a phenomenon it calls "cash drag." The cost compounds quietly: cash might earn around 4% a year today, while a broad stock-market fund has historically returned roughly 10% a year on average over the long run. Across the years a rollover can sit forgotten, that gap adds up to real money left on the table — without the saver ever making a decision.

## What to actually do

- **Check what you're holding.** Log into every old account — 401(k)s from past jobs, any IRAs — and look at what each is invested in. If you see "cash" or "money market," that's the signal to act.
- **Pick an investment.** If choosing feels paralyzing, a **target-date fund** matched to roughly when you'll retire is a sensible, diversified default that rebalances itself over time.
- **Mind the fees.** Costs vary by provider; many brokerages now charge little or nothing to hold an IRA, so it's worth comparing.
- **Consolidate.** Scattering money across several old 401(k)s and IRAs makes it easy to lose track. Combining them into one IRA makes it simpler to monitor and rebalance.
- **Know the tax angle.** Rolling a traditional 401(k) into a traditional IRA is generally tax-free; rolling it into a **Roth** IRA triggers a tax bill that year on the converted amount, so plan for it.

## The takeaway

The rise of the IRA is, on paper, a good-news story: it means Americans are accumulating large retirement balances. But an IRA is only as powerful as what's inside it. The single most valuable thing many savers can do is unglamorous — log in, find any cash that's quietly sitting out of the market, and put it to work. The money is already yours; the only question is whether it's actually invested.

## Sources

- [Quarterly Retirement Market Data](https://www.ici.org/research/stats/retirement)
- [Out of sight, out of market: the IRA cash drag](https://corporate.vanguard.com/content/corporatesite/us/en/corp/articles/out-sight-out-market-ira-cash-drag.html)