# 401(k) providers: what AI models recommend, October 2026

HR AI Recommendation Index, October 2026 Edition. Asked as "401(k) provider" and as "workplace retirement plan provider", six framings each, to fourteen models with search on, on behalf of a mid-market B2B company. Added to the October 2026 Edition on October 4, 2026; its answers are read by the distilled judge (ai-indexes-judge-qwen3-14b-run3), not the claude-opus-5 judge of the earlier categories. Page: https://hr-ai-index.com/rewards/401k-providers/

**Standing:** Human Interest (tied with Guideline) leads with 20% of first choices; verdict contested. 55 first choices across the direct, paraphrase, budget and scale prompts.

## First-choice share

| # | Product | Share | Negative rate | Labels |
|---|---|---|---|---|
| 1 | Human Interest | 20% | 7% | 42 |
| 2 | Guideline | 20% | 9% | 32 |
| 3 | ADP Retirement Services | 16% | 12% | 41 |
| 4 | Fidelity Investments | 13% | 4% | 23 |
| 5 | Fidelity Advantage 401 | 9% | 0% | 36 |
| 6 | Empower Retirement | 7% | 0% | 38 |
| 7 | Vanguard | 5% | 4% | 46 |
| 8 | Principal | 2% | 8% | 13 |
| 9 | Charles Schwab | 0% | 0% | 18 |
| 10 | Betterment at Work | 0% | 10% | 10 |
| 11 | T. Rowe Price | 0% | 20% | 10 |
| 12 | Paychex | 0% | 27% | 11 |

## Each model's first choice on the direct prompt

- Claude Haiku 4.5: Human Interest; alternatives Fidelity Investments, Principal, Vanguard
- GPT-5.4 mini: ADP Retirement Services; alternatives Empower Retirement, Gusto, ShareBuilder 401k
- Gemini 3.5 Flash: Human Interest; alternatives ADP Retirement Services, Fidelity Investments, Principal Financial Group
- Perplexity Sonar: ADP Retirement Services, Human Interest; alternatives Empower Retirement, Fidelity Advantage 401, John Hancock, Securian Financial
- Grok 4.1 Fast: Guideline, Human Interest; alternatives ADP Retirement Services, Charles Schwab, Fidelity Advantage 401, Principal
- Mistral Small: Fidelity Advantage 401; alternatives ADP Retirement Services, Empower Retirement
- DeepSeek V4 Flash: Fidelity Investments, Guideline, Human Interest; alternatives ADP Retirement Services, Empower Retirement, T. Rowe Price
- Llama 4 Maverick: no first choice
- Qwen 3.7 Flash: Fidelity Investments, Guideline, Lighthouse Group; alternatives Charles Schwab, Vanguard
- Kimi K2: Fidelity Investments; alternatives ADP Retirement Services, Empower Retirement, T. Rowe Price, Vanguard
- GLM 4.7 FlashX: Human Interest; alternatives ADP Retirement Services, Fidelity Investments, Vanguard
- MiniMax M2.5: Human Interest; alternatives Empower Retirement, T. Rowe Price
- GPT-6 Luna: ADP 401(k) Premier; alternatives Empower Retirement, Fidelity Workplace, Principal
- Muse Glimmer 30B: Empower Retirement, Fidelity Investments; alternatives ADP Retirement Services, Employee Fiduciary, Guideline, Human Interest

## Sources the answers cite

74 of 84 answers came back with a source list, from 14 of 14 models. Sites named in the most answers:

- spotsaas.com: 37 answers, 49 citations
- adp.com: 36 answers, 54 citations
- uschamber.com: 35 answers, 35 citations
- betterment.com: 29 answers, 43 citations
- fidelity.com: 28 answers, 29 citations
- forbes.com: 27 answers, 32 citations
- fitsmallbusiness.com: 24 answers, 24 citations
- humaninterest.com: 22 answers, 44 citations

Pages named in the most answers:

- https://uschamber.com/co/run/human-resources/employee-retirement-providers (35 answers)
- https://adp.com/what-we-offer/benefits/retirement/401k.aspx (33 answers)
- https://betterment.com/top-401ks-for-small-businesses-in-2026 (24 answers)
- https://fitsmallbusiness.com/best-401k-companies (24 answers)
- https://fidelity.com/retirement-ira/small-business/compare-retirement-plans (23 answers)
- https://forbes.com/advisor/retirement/best-401k-plans (22 answers)
- https://goldenwealthcapital.com/blog/the-top-401k-providers-proven-list-from-a-401-k-expert (18 answers)
- https://myshortlister.com/401-k-plan/vendor-list (18 answers)
- https://spotsaas.com/blog/10-best-401k-providers-2026 (17 answers)
- https://basiccapital.com/learn/best-401k-providers-for-mid-market-companies-fees-flexibility-support (15 answers)

## Warned against

- MassMutual: 5 of 6 labels negative. "frequently mentioned as among the worst offenders due to their high administrative costs, expensive fund options, and sometimes opaque fee structures" (Mistral Small, negative prompt)
- John Hancock: 4 of 9 labels negative. "Multiple financial advisors specifically recommend avoiding John Hancock for 401(k) plans due to service and fee issues." (DeepSeek V4 Flash, negative prompt)
- Ascensus: 3 of 5 labels negative. "Ascensus, which handled the Vanguard transfer of 401(k)s so badly that a class action lawsuit may be in the works." (Claude Haiku 4.5, negative prompt)
- Guideline: 3 of 32 labels negative. "BBB customer reviews include stark warnings, e.g.: "Avoid at all costs." "You will never be able to get your money out."" (Muse Glimmer 30B, negative prompt)

## Record

- Method: https://hr-ai-index.com/methodology/
- Raw judge labels and full responses: https://hr-ai-index.com/data/
- License: CC BY 4.0. Cite as HR AI Recommendation Index, October 2026 Edition, hr-ai-index.com.