Pick the Right One: Don’t Confuse E-TRADE Solo 401k with Advanced Solo 401k Setup

Not all Solo 401k plans are created equal — and for self-employed individuals and solopreneurs, the difference can mean tens of thousands of dollars in missed tax-advantaged opportunities. If you’ve been thinking about opening a Solo 401k directly with E-TRADE, this guide will explain exactly what you get, what you don’t get, and why the underlying plan documents are the most important factor to consider.

In this post — drawn directly from a live Q&A webinar hosted by My Solo 401k Financial — we break down the critical distinctions between a basic brokerage Solo 401k (like the one offered directly by E-TRADE) and a fully-featured, individually designed Solo 401k plan. The concepts apply broadly to basic plans at Fidelity, Schwab, Vanguard, and similar providers as well.

Who Is Eligible to Open a Solo 401k?

Before exploring plan features, it helps to understand the eligibility rules. A Solo 401k is a 401(k) plan specifically designed for self-employed individuals. Two requirements must be met:

1. Earned self-employment income — This is income from your self-employed business:
   • Sole proprietor / single-member LLC: Line 31 of Schedule C
   • S-Corp or C-Corp (or LLC taxed as such): W-2 wages from your own business
   • Partnership / multi-member LLC: Line 14 of the K-1 from the partnership
2. No non-owner, non-spouse full-time W-2 employees — A spouse or co-owner actively working in the business does not disqualify the plan. Only unrelated full-time employees would.

Why the Plan Documents Are Everything

A Solo 401k is a legal entity — and like any legal entity, its capabilities are defined entirely by its governing documents. What you’re allowed to do with your plan depends on what those underlying documents permit.

When you open a Solo 401k directly with E-TRADE, E-TRADE uses their own prototype documents — a standardized, basic set designed to accommodate the broadest possible customer base with minimal complexity. However, what many people don’t realize is that you are not required to use E-TRADE’s documents. You can obtain your plan documents from a third-party plan provider like My Solo 401k Financial and still open your brokerage accounts at E-TRADE.

Basic E-TRADE Solo 401k vs. Advanced Solo 401k: Feature Comparison

Here’s a side-by-side comparison of what you get with a basic brokerage Solo 401k versus an individually designed plan from My Solo 401k Financial:

Top Advanced Features of an Individually Designed Solo 401k

1. Alternative Investments

One of the most powerful — and frequently requested — capabilities of an advanced Solo 401k is the ability to invest in assets beyond publicly traded stocks and bonds. With an individually designed plan from My Solo 401k Financial, participants can invest in:

• Real estate (residential and commercial)
• Cryptocurrency
• Private placements and private equity
• Pre-IPO stock (e.g., companies like SpaceX before going public)
• Precious metals
• And many other IRS-permitted alternative assets

Basic plans from E-TRADE, Fidelity, or Schwab restrict participants to their standard brokerage platform offerings. An individually designed plan removes those walls.

2. Mega Backdoor Roth Solo 401k Contributions

The Mega Backdoor Roth strategy is a two-step process that allows self-employed individuals to contribute significantly more to a Roth account than standard contribution limits allow:

1. Step 1 – Make a Voluntary After-Tax Contribution: Contribute up to 100% of self-employment compensation, up to the overall IRS limit — $72,000 for 2026 — into a voluntary after-tax Solo 401k sub-account.
2. Step 2 – Convert to Roth: Transfer those voluntary after-tax funds either to a Roth Solo 401k or a Roth IRA, where they grow potentially tax-free.

My Solo 401k Financial was the first Solo 401k provider to offer a Solo 401k plan that allows for Mega Backdoor Roth contributions. The company provides deep expertise in helping both clients and their advisors navigate every step of the process — including the required 1099-R tax form issuance.

3. In-Plan Roth Conversion

In addition to Mega Backdoor Roth contributions, an advanced Solo 401k plan from My Solo 401k Financial also allows for in-plan Roth conversions — moving pre-tax funds already in the plan directly into a Roth sub-account within the same Solo 401k. This is a powerful tax-planning tool, especially for years when income is lower than usual.

4. Solo 401k Participant Loans

An individually designed Solo 401k plan from My Solo 401k Financial allows participants to borrow from their own plan. The rules permit loans up to the lesser of $50,000 or 50% of the vested account balance. The loan must be repaid with interest — the prime rate plus 1% or a CD rate plus 2%— paid back to your own plan rather than to a bank.

SECURE Act Tax Credits: $500/Year for Qualifying Plans

Under the SECURE Act, eligible self-employed businesses can claim a $500 annual tax credit beginning with the year their plan is established. My Solo 401k Financial includes the required automatic enrollment feature in its plan documents to make clients eligible for this credit.

How the Auto-Enrollment Feature Works

The automatic enrollment feature establishes a default contribution percentage of 3%. However, as the plan participant, you have the right to opt out of that default and contribute on your own schedule — in any amount, subject to IRS limits and deadlines. The key point: exercising your right to opt out does not eliminate the credit. Your business still included the auto-enrollment feature in its plan, so it remains eligible for the $500 annual tax credit.

Works With Your Existing Advisor and Brokerage

My Solo 401k Financial is a plan document provider only — not an investment advisor and not an account custodian. This makes the company fully complementary to any existing advisor relationships. Whether your advisor custodies at:

• E-TRADE
• Fidelity / Fidelity Institutional
• Schwab / Schwab Institutional
• Altruist
• Vanguard
• Any of hundreds of local banks or credit unions

…My Solo 401k Financial can help establish the plan documents and assist in opening the appropriate accounts at the institution of choice. Advisors retain full investment management authority, while the client gains access to the full suite of advanced features.