# 401(k) providers for small business buyers: 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 small 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/smb/

**Standing:** Guideline leads with 43% of first choices; verdict clear leader. 53 first choices across the direct, paraphrase, budget and scale prompts.

## First-choice share

| # | Product | Share | Negative rate | Labels |
|---|---|---|---|---|
| 1 | Guideline | 43% | 8% | 52 |
| 2 | Human Interest | 15% | 0% | 49 |
| 3 | Fidelity Advantage 401 | 11% | 7% | 45 |
| 4 | ADP Retirement Services | 8% | 28% | 47 |
| 5 | Betterment at Work | 2% | 0% | 21 |
| 6 | Employee Fiduciary | 2% | 0% | 17 |
| 7 | Vanguard | 2% | 19% | 27 |
| 8 | Ubiquity | 0% | 0% | 11 |
| 9 | Paychex | 0% | 52% | 21 |

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

- Claude Haiku 4.5: Guideline; alternatives ADP Retirement Services, Human Interest
- GPT-5.4 mini: Guideline, Human Interest; alternatives ADP Retirement Services, ShareBuilder 401k
- Gemini 3.5 Flash: Guideline; alternatives Betterment at Work, Human Interest, Ubiquity Retirement + Savings
- Perplexity Sonar: Fidelity Advantage 401; alternatives ADP Retirement Services, Guideline
- Grok 4.1 Fast: Guideline, Human Interest; alternatives ADP Starter-k, Fidelity Advantage 401, ForUsAll, Vanguard
- Mistral Small: ADP Retirement Services, Fidelity Advantage 401; alternatives Paychex
- DeepSeek V4 Flash: Guideline; alternatives Employee Fiduciary, Human Interest
- Llama 4 Maverick: no first choice
- Qwen 3.7 Flash: Guideline; alternatives Fidelity Advantage 401, Human Interest, Schwab
- Kimi K2: Guideline; alternatives Betterment at Work, Fidelity Advantage 401, Human Interest
- GLM 4.7 FlashX: Guideline, Human Interest; alternatives ADP Retirement Services, Betterment at Work, Fidelity Advantage 401, Vanguard
- MiniMax M2.5: Fidelity Advantage 401, Merrill; alternatives ADP Retirement Services
- GPT-6 Luna: Betterment at Work; alternatives Human Interest Complete
- Muse Glimmer 30B: Guideline, Human Interest; alternatives Fidelity Investments, Vanguard

## Sources the answers cite

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

- adp.com: 44 answers, 79 citations
- fidelity.com: 44 answers, 48 citations
- betterment.com: 42 answers, 64 citations
- spotsaas.com: 37 answers, 55 citations
- myubiquity.com: 34 answers, 39 citations
- uschamber.com: 32 answers, 32 citations
- duncanins.com: 23 answers, 23 citations
- employeefiduciary.com: 22 answers, 42 citations

Pages named in the most answers:

- https://fidelity.com/retirement-ira/small-business/compare-retirement-plans (40 answers)
- https://betterment.com/top-401ks-for-small-businesses-in-2026 (37 answers)
- https://adp.com/what-we-offer/benefits/retirement/401k.aspx (34 answers)
- https://uschamber.com/co/run/human-resources/employee-retirement-providers (32 answers)
- https://myubiquity.com/resources/best-small-business-401-k-providers (28 answers)
- https://duncanins.com/best-401-k-plan-for-small-business (23 answers)
- https://spotsaas.com/blog/5-best-401k-providers-for-small-businesses (22 answers)
- https://fitsmallbusiness.com/best-401k-companies (21 answers)
- https://betterment.com/top-401k-providers-for-small-business-setup-in-2026 (20 answers)
- https://forbes.com/advisor/retirement/best-401k-plans (19 answers)

## Warned against

- ADP Retirement Services: 13 of 47 labels negative. "Criticized for high fees, poor customer service, limited investment options, and frustrating rollover processes" (GLM 4.7 FlashX, negative prompt)
- Paychex: 11 of 21 labels negative. "Payroll-Bundled Providers (Unless negotiated carefully) * Examples: Paychex, ADP * Why to avoid/be cautious:" (Gemini 3.5 Flash, negative prompt)
- Vanguard: 5 of 27 labels negative. "Avoid for plan administration—not their core competency" (Kimi K2, negative prompt)
- Guideline: 4 of 52 labels negative. "reviews (e.g., Accio Work, Reddit) cite terrible support, difficulties with transfers/rollovers, and hidden gotchas" (Grok 4.1 Fast, 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.