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Print · September 2026 Edition

Lob vs Sendoso

Zero of twelve models named Lob first on the direct prompt; one named Sendoso. Both were named by all twelve models and Lob carries 48 labels and Sendoso 45, so the shares are not directly comparable.

Lob

criticized challenger

Named in one category this edition.

Sendoso

accepted challenger

Named in one category this edition.

First-choice share9%4%Of first choices across the direct, paraphrase, budget and scale prompts, 0 to 100.

Negative rate27%22%Negative labels as a share of the product's labels, 0 to 100.

Rank in category#2#5A position in a field of 11; printed, not drawn.

Labels4845A count; the two differ.

The two percentage rows are drawn on one 0 to 100 track, Lob reading right to left. Rank and label count are printed, not drawn.Postalytics was named alongside these two in ten of the twelve direct answers. Postalytics vs Lob · Postalytics vs Sendoso · Lob vs Stannp

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; every quote names the model and the prompt it came from. Both figures come from the print page.

By framing

How many of the twelve models made each the first choice, per way of asking, and how many argued against it.

LobFirst choices, of twelve modelsSendoso

Direct012 against Sendoso

Paraphrase211 against Lob · 1 against Sendoso

Comparative52

Budget-constrained003 against Lob · 1 against Sendoso

Scale-constrained20

Negative009 against Lob · 6 against Sendoso

Bars are first choices, 0 to 12 each sideModels that argued againstA model can name both, so the two sides of a row do not sum to twelve.

Across every category in the September 2026 Edition, Lob and Sendoso were named in the same answer 106 times, of the 154 answers naming Lob and the 125 naming Sendoso. In those answers Sendoso took the first choice four times and Lob twenty-nine.

Every model, every framing

The seventy-two answers behind the chart above, one cell each: where Lob and Sendoso stood in it.

Model	DirectLO	ParaphraseLO	ComparativeLO	Budget-constrainedLO	Scale-constrainedLO	NegativeLO
Claude Haiku 4.5			LO
GPT-5.4 mini		LO	LO
Gemini 3.5 Flash	LO	LO	LO	LO		LO
Perplexity Sonar	LO		LO	LO		LO
Grok 4.1 Fast	LO	LO	LO	LO	LO	LO
Mistral Small	LO		LO			LO
DeepSeek V4 Flash	LO	LO	LO	LO	LO	LO
Llama 4 Maverick
Qwen 3.7 Flash		LO	LO			LO
Kimi K2	LO	LO	LO	LO	LO	LO
GLM 4.7 FlashX	LO		LO			LO
MiniMax M2.5	LO	LO	LO			LO

LO Lob

SendosoLO first choiceLO named as an alternativeLO argued againstblank: not namedEach cell is one answer, Lob on the left and Sendoso on the right.

The direct prompt

The plain question, one answer per model, grouped by where Lob and Sendoso stood in it.

Sendoso first, Lob not the choice

1 of 12 modelsLob was named in the answer but not as the choice, or not at all.

GPT-5.4 miniSendoso alternatives: PFL

Neither was the first choice, one was named

10 of 12 modelsThe answer put something else first and named one of the two as an alternative.

Claude Haiku 4.5PFL alternatives: PostGrid, Sendoso

Gemini 3.5 FlashPostalytics, Reachdesk alternatives: Alyce, Lob, Postal

Perplexity SonarPostalytics alternatives: DirectMail.io, Lob, Sendoso

Grok 4.1 FastPostalytics alternatives: Lob, PostGrid, Sendoso

Mistral SmallPostalytics alternatives: Lob, PostGrid, Sendoso

DeepSeek V4 FlashPostalytics alternatives: Lob, PFL, Reachdesk, Sendoso

Qwen 3.7 FlashPostalytics alternatives: Click2Mail, LetterStream, Sendoso

Kimi K2Postalytics alternatives: Lob, PFL, Sendoso

GLM 4.7 FlashXPostalytics alternatives: Lob, PostGrid, Postal, Reachdesk

MiniMax M2.5Postalytics alternatives: Lob, Postal, Sendoso, Stannp

Neither was named

1 of 12 modelsThe answer made no first choice from these two in this category.

Llama 4 MaverickPostalytics alternatives: Magileads

Bold names in an answer are the products the judge labeled a first choice; a model naming several gives each of them that label. The full answer text for every row is in the record.

By buyer segment

The same question asked on behalf of a different buyer. Each standing is computed within its segment and they are never added together. The figures above are the mid-market standing, which is the one the category orders by.

Small business

Lob leads by eight points.

Lob#3 of 9

Sendoso#7 of 9

The full small business standing →

Mid-marketThe figures above

Lob leads by four points.

Lob#2 of 11

Sendoso#5 of 11

The full mid-market standing →

Enterprise

Lob leads by twenty-six points.

Lob#1 of 9

Sendoso#3 of 9

The full enterprise standing →

What the models said about Lob

Every negative label with a quote, up to three, then the highest-weighted positives, up to three. Six of eight in this category shown.

“Platforms to Avoid on a Tight Budget- Lob — Great API, but the $260–550/month platform fee” DeepSeek V4 Flash · budget prompt · hard negative

“SaaS "Subscription Traps" to Avoid on a Budget ... they are not ideal for tight budgets” Gemini 3.5 Flash · budget prompt · hard negative

“Steep Learning Curve: Complex API documentation and lack of guidance for non-developers” GLM 4.7 FlashX · negative prompt · hard negative

“Postalytics or Lob are strong starting points if you want CRM-connected marketing automation” Kimi K2 · scale prompt · first choice

“1. Lob - API-First Platform ... Lob - Complete REST API, webhook support, postal IQ routing” GLM 4.7 FlashX · comparative prompt · first choice

“Choose PostGrid or Lob if you want API-first, developer-controlled automation” Perplexity Sonar · comparative prompt · first choice

What the models said about Sendoso

Every negative label with a quote, up to three, then the highest-weighted positives, up to three. Six of eight in this category shown.

“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

Also compared

Postalytics vs Lob Postalytics vs Sendoso Lob vs Stannp Lob vs PostGrid Lob vs Click2Mail Lob vs PFL Lob vs Mailjoy Stannp vs Sendoso PostGrid vs Sendoso Sendoso vs Click2Mail Sendoso vs PFL Sendoso vs Mailjoy All twenty-eight head-to-head pages and the full direct mail standing

Comparisons are drawn for the top eight products in each category, each against each. The output is the models' output; nothing here is a recommendation by the index.