# Sendoso vs Mailjoy: which do AI models recommend for direct mail, September 2026

GTM AI Recommendation Index, September 2026 Edition, Print. One of twelve models named Sendoso first on the direct prompt; zero named Mailjoy. Page: https://gtm-ai-index.com/marketing/print/sendoso-vs-mailjoy/

| | First-choice share | Rank | Negative rate | Labels | Models naming it |
|---|---|---|---|---|---|
| Sendoso | 4% | #5 of 11 | 22% | 45 | 12 of 12 |
| Mailjoy | 2% | #8 of 11 | 11% | 19 | 11 of 12 |

## The direct prompt, model by model

- GPT-5.4 mini: sendoso first (first choices: Sendoso) (alternatives: PFL)
- Claude Haiku 4.5: neither first, one named (first choices: PFL) (alternatives: PostGrid, Sendoso)
- Perplexity Sonar: neither first, one named (first choices: Postalytics) (alternatives: DirectMail.io, Lob, Sendoso)
- Grok 4.1 Fast: neither first, one named (first choices: Postalytics) (alternatives: Lob, PostGrid, Sendoso)
- Mistral Small: neither first, one named (first choices: Postalytics) (alternatives: Lob, PostGrid, Sendoso)
- DeepSeek V4 Flash: neither first, one named (first choices: Postalytics) (alternatives: Lob, PFL, Reachdesk, Sendoso)
- Qwen 3.7 Flash: neither first, one named (first choices: Postalytics) (alternatives: Click2Mail, LetterStream, Sendoso)
- Kimi K2: neither first, one named (first choices: Postalytics) (alternatives: Lob, PFL, Sendoso)
- MiniMax M2.5: neither first, one named (first choices: Postalytics) (alternatives: Lob, Postal, Sendoso, Stannp)
- Gemini 3.5 Flash: neither named (first choices: Postalytics, Reachdesk) (alternatives: Alyce, Lob, Postal)
- Llama 4 Maverick: neither named (first choices: Postalytics) (alternatives: Magileads)
- GLM 4.7 FlashX: neither named (first choices: Postalytics) (alternatives: Lob, PostGrid, Postal, Reachdesk)

## What the models said about Sendoso

- "Platforms with Significant Concerns ... Sendoso (and Postal.io - now acquired by Sendoso) Key Red Flags: Non-refundable prepaid balances that expire" (Kimi K2, negative prompt, hard negative)
- "Non-refundable preloaded funds: Once you add funds to the platform, you cannot withdraw them. This is a major lock-in risk" (DeepSeek V4 Flash, negative prompt, hard negative)
- "High Costs: Can be expensive, especially for larger teams" (GLM 4.7 FlashX, negative prompt, hard negative)
- "Sendoso is the safest "best overall" pick if you want a broad, mature direct mail automation platform" (GPT-5.4 mini, direct prompt, first choice)
- "Sendoso is the dominant ecosystem for "sending management"" (Gemini 3.5 Flash, comparative prompt, first choice)
- "Sendoso is a top-rated direct mail automation platform" (Claude Haiku 4.5, comparative prompt, first choice)

## What the models said about Mailjoy

- "pricing traps for your size: Mailjoy, Click2Mail, Printfection ... likely lack the governance, API depth, and attribution you need" (DeepSeek V4 Flash, scale prompt, soft negative)
- "Mailform, Mailjoy, and similar lightweight tools if you need enterprise governance, complex approvals, or robust automation" (Perplexity Sonar, negative prompt, soft negative)
- "If you want free/cheap testing: Start with Mailjoy or Postalytics free plan" (Mistral Small, budget prompt, first choice)
- "if you are looking for a platform with a simple, self-serve interface, Mailjoy or Click2Mail may be more suitable" (Llama 4 Maverick, negative prompt, alternative)
- "You want simple, self-serve postcards/letters: → Mailjoy or Click2Mail" (Qwen 3.7 Flash, comparative prompt, alternative)

Share is the count of first choices across the direct, paraphrase, budget and scale prompts over all twelve models, for a mid-market B2B company; rank is within the category. Comparisons are drawn for the top eight products in each category. Published under CC BY 4.0; the output is the models' output, and nothing here is a recommendation by the index.