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Index › Tax and compliance › Corporate tax provision › Thomson Reuters ONESOURCE vs Vertex
Corporate tax provision · September 2026 Edition

Thomson Reuters ONESOURCE vs Vertex

Zero of twelve models named Thomson Reuters ONESOURCE first on the direct prompt; zero named Vertex. Thomson Reuters ONESOURCE was named by nine of the twelve models and Vertex by seven and Thomson Reuters ONESOURCE carries 19 labels and Vertex 10, so the shares are not directly comparable.

Thomson Reuters ONESOURCE

accepted challenger

Named in three categories this edition.

Vertex

criticized challenger

Named in three categories this edition.

First-choice share10%2%Of first choices across the direct, paraphrase, budget and scale prompts, 0 to 100.
Negative rate16%40%Negative labels as a share of the product's labels, 0 to 100.
Rank in category#3#6A position in a field of 9; printed, not drawn.
Labels1910A count; the two differ.
The two percentage rows are drawn on one 0 to 100 track, Thomson Reuters ONESOURCE reading right to left. Rank and label count are printed, not drawn.Thomson Reuters ONESOURCE Tax Provision was named alongside these two in ten of the twelve direct answers. Thomson Reuters ONESOURCE Tax Provision vs Thomson Reuters ONESOURCE · Thomson Reuters ONESOURCE Tax Provision vs Vertex · Bloomberg Tax Provision vs Thomson Reuters ONESOURCE

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 corporate tax provision page.

By framing

How many of the twelve models made each the first choice, per way of asking, and how many argued against it.
Thomson Reuters ONESOURCEFirst choices, of twelve modelsVertex
Direct001 against Vertex
Paraphrase41
Comparative00
Budget-constrained003 against Thomson Reuters ONESOURCE · 3 against Vertex
Scale-constrained00
Negative00
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, Thomson Reuters ONESOURCE and Vertex were named in the same answer fifty-four times, of the 101 answers naming Thomson Reuters ONESOURCE and the 192 naming Vertex. In those answers Vertex took the first choice nine times and Thomson Reuters ONESOURCE four.

Every model, every framing

The seventy-two answers behind the chart above, one cell each: where Thomson Reuters ONESOURCE and Vertex stood in it.
ModelDirectParaphraseComparativeBudget-constrainedScale-constrainedNegative
Claude Haiku 4.5
GPT-5.4 mini
Gemini 3.5 Flash
Perplexity Sonar
Grok 4.1 Fast
Mistral Small
DeepSeek V4 Flash
Llama 4 Maverick
Qwen 3.7 Flash
Kimi K2
GLM 4.7 FlashX
MiniMax M2.5
Thomson Reuters ONESOURCE Vertex first choice named as an alternative argued againstblank: not namedEach cell is one answer, Thomson Reuters ONESOURCE on the left and Vertex on the right.

The direct prompt

The plain question, one answer per model, grouped by where Thomson Reuters ONESOURCE and Vertex stood in it.

Neither was the first choice, one was named

2 of 12 modelsThe answer put something else first and named one of the two as an alternative.
Claude Haiku 4.5no first choice alternatives: Bloomberg Tax Provision, CSC Corptax, Longview Tax, Thomson Reuters ONESOURCE
Qwen 3.7 FlashLongview Tax alternatives: Bloomberg Tax Provision, CSC Corptax, Thomson Reuters ONESOURCE

Neither was named

10 of 12 modelsThe answer made no first choice from these two in this category.
GPT-5.4 miniThomson Reuters ONESOURCE Tax Provision alternatives: CCH Axcess/ProSystem fx tax provision offerings, Longview Tax, ONESOURCE Income Tax / Direct Tax Essential
Gemini 3.5 FlashBloomberg Tax Provision alternatives: Exactera Tax Provision, Longview Tax, Thomson Reuters ONESOURCE Tax Provision, Vena Solutions
Perplexity SonarThomson Reuters ONESOURCE Tax Provision alternatives: CSC Corptax, Wolters Kluwer CCH Tagetik Tax Provision & Reporting
Grok 4.1 FastThomson Reuters ONESOURCE Tax Provision alternatives: TaxPoint, Taxfyle, Vertex Tax Accounting
Mistral SmallThomson Reuters ONESOURCE Tax Provision alternatives: Sovos Tax Provision, Vertex Tax Accounting
DeepSeek V4 FlashBloomberg Tax Provision, Thomson Reuters ONESOURCE Tax Provision alternatives: Sovos Tax Provision, Vertex Tax Accounting
Llama 4 MaverickThomson Reuters ONESOURCE Tax Provision alternatives: Avalara, CCH Axcess Tax, Taxfyle
Kimi K2Thomson Reuters ONESOURCE Tax Provision alternatives: CCH Tagetik, FloQast Tax Provision, Longview Tax, Lucasys Tax Provision, Sovos Tax Provision
GLM 4.7 FlashXThomson Reuters ONESOURCE Tax Provision alternatives: Bloomberg Tax Provision, Longview Tax, Sovos Tax Provision
MiniMax M2.5Bloomberg Tax Provision, Thomson Reuters ONESOURCE Tax Provision alternatives: CCH Tagetik Tax Provision & Reporting, Taxfyle, Vertex Tax Accounting

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
Thomson Reuters ONESOURCE leads by two points.
Thomson Reuters ONESOURCE2%#8 of 9
Vertex0%#– of 9
The full small business standing →
Mid-marketThe figures above
Thomson Reuters ONESOURCE leads by seven points.
Thomson Reuters ONESOURCE10%#3 of 9
Vertex2%#6 of 9
The full mid-market standing →
Enterprise
Thomson Reuters ONESOURCE leads by eighteen points.
Thomson Reuters ONESOURCE20%#2 of 9
Vertex2%#8 of 9
The full enterprise standing →

What the models said about Thomson Reuters ONESOURCE

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

“Enterprise Options to AVOID on a Limited Budget | Thomson Reuters ONESOURCE | $200K–$2M+/year” Kimi K2 · budget prompt · hard negative
“Avoid: Longview, ONESOURCE, Workiva, Oracle Tax Reporting, and Corptax.” DeepSeek V4 Flash · budget prompt · hard negative
“cannot justify the six-figure price tag of enterprise suites like Bloomberg or Thomson Reuters ONESOURCE” Qwen 3.7 Flash · budget prompt · soft negative
“Choose Thomson Reuters ONESOURCE if you are a larger, audited mid-market C-Corp with multiple subsidiaries” Gemini 3.5 Flash · paraphrase prompt · first choice
“I'd recommend Thomson Reuters ONESOURCE as the top choice for income tax compliance software” Grok 4.1 Fast · paraphrase prompt · first choice
“Corporate income tax (direct tax) | Thomson Reuters ONESOURCE or Vertex” GLM 4.7 FlashX · paraphrase prompt · first choice

What the models said about Vertex

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

“Enterprise-focused, indirect tax only (no provision)” Kimi K2 · budget prompt · hard negative
“consider Vertex for indirect tax, but it is not the clearest provision-first choice from the sources I found” GPT-5.4 mini · direct prompt · soft negative
“Corporate income tax (direct tax) | Thomson Reuters ONESOURCE or Vertex” GLM 4.7 FlashX · paraphrase prompt · first choice
Also compared
Thomson Reuters ONESOURCE Tax Provision vs Thomson Reuters ONESOURCEThomson Reuters ONESOURCE Tax Provision vs VertexBloomberg Tax Provision vs Thomson Reuters ONESOURCEBloomberg Tax Provision vs VertexThomson Reuters ONESOURCE vs Longview TaxThomson Reuters ONESOURCE vs AvalaraLongview Tax vs VertexAvalara vs VertexAll fifteen head-to-head pages and the full corporate tax provision 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.