# Corporate tax provision for enterprise buyers: what AI models recommend, October 2026

Finance AI Recommendation Index, October 2026 Edition. Asked as "corporate tax provision software" and as "income tax compliance software", six framings each, to fourteen models with search on, on behalf of an enterprise B2B company. Page: https://finance-ai-index.com/tax/corporate-tax-provision/enterprise/

**Standing:** Thomson Reuters ONESOURCE Tax Provision leads with 46% of first choices; verdict clear leader. 50 first choices across the direct, paraphrase, budget and scale prompts.

## First-choice share

| # | Product | Share | Negative rate | Labels |
|---|---|---|---|---|
| 1 | Thomson Reuters ONESOURCE Tax Provision | 46% | 7% | 57 |
| 2 | CSC Corptax | 12% | 3% | 35 |
| 3 | Bloomberg Tax Provision | 4% | 14% | 36 |
| 4 | Wolters Kluwer CCH Tagetik Tax Provision | 4% | 9% | 11 |
| 5 | Sovos Tax Provision | 2% | 4% | 25 |
| 6 | Longview Tax | 2% | 21% | 29 |
| 7 | Vertex | 2% | 24% | 17 |
| 8 | Avalara | 2% | 42% | 12 |
| 9 | Oracle Tax Reporting | 0% | 0% | 19 |

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

- Claude Haiku 4.5: Bloomberg Tax Provision, ONESOURCE Corporate Tax; alternatives CSC Corptax, Oracle Tax Reporting
- GPT-5.4 mini: Thomson Reuters ONESOURCE Tax Provision; alternatives CCH Tagetik Tax Provision & Reporting, CSC Corptax, Longview Tax
- Gemini 3.5 Flash: Thomson Reuters ONESOURCE Tax Provision; alternatives Bloomberg Tax Provision, CSC Corptax, Longview Tax, OneStream
- Perplexity Sonar: Thomson Reuters ONESOURCE Tax Provision; alternatives Bloomberg Tax Provision, CSC Corptax Tax Provision
- Grok 4.1 Fast: Thomson Reuters ONESOURCE Tax Provision; alternatives Sovos Tax Provision, Vertex Tax Accounting
- Mistral Small: Thomson Reuters ONESOURCE Tax Provision; alternatives Sovos Tax Provision, Vertex Tax Accounting
- DeepSeek V4 Flash: Thomson Reuters ONESOURCE Tax Provision; alternatives CSC Corptax, Oracle Tax Reporting, Sovos Tax Provision
- Llama 4 Maverick: no first choice
- Qwen 3.7 Flash: Thomson Reuters CORPTAX; alternatives Indico Data Solutions, Workiva Tax and Provision
- Kimi K2: Thomson Reuters ONESOURCE Tax Provision; alternatives Bloomberg Tax Provision, CCH Tagetik Tax Provision & Reporting, Vertex O Series
- GLM 4.7 FlashX: Wolters Kluwer CCH Tagetik Tax Provision; alternatives Bloomberg Tax Provision, Longview Tax, Sovos Tax Provision, Thomson Reuters ONESOURCE Tax Provision
- MiniMax M2.5: Bloomberg Tax Provision, Thomson Reuters ONESOURCE Tax Provision; alternatives CSC Corptax, Sovos Tax Provision
- GPT-6 Luna: Thomson Reuters ONESOURCE Tax Provision; alternatives CSC Corptax AIT, Longview Tax, Oracle Tax Reporting
- Muse Glimmer 30B: Thomson Reuters ONESOURCE Tax Provision; alternatives CSC Corptax, OneStream Tax Provision

## Sources the answers cite

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

- tax.thomsonreuters.com: 60 answers, 141 citations
- worldmetrics.org: 42 answers, 107 citations
- gitnux.org: 40 answers, 77 citations
- finance-ai-index.com: 30 answers, 49 citations
- zipdo.co: 28 answers, 42 citations
- theaccountingclub.net: 25 answers, 25 citations
- pro.bloombergtax.com: 24 answers, 49 citations
- thecfoclub.com: 20 answers, 23 citations

Pages named in the most answers:

- https://tax.thomsonreuters.com/en/products/onesource-tax-provision (29 answers)
- https://worldmetrics.org/best/corporate-tax-provision-software (29 answers)
- https://finance-ai-index.com/tax/corporate-tax-provision/enterprise (28 answers)
- https://tax.thomsonreuters.com/en/tax-accounting/tax-software-for-larger-businesses (27 answers)
- https://theaccountingclub.net/best-corporate-tax-software (25 answers)
- https://worldmetrics.org/best/tax-provision-software (23 answers)
- https://gitnux.org/best/tax-provision-software (22 answers)
- https://cbh.com/insights/articles/tax-provision-automation-guide-benefits-software-roadmap (16 answers)
- https://pickmysoft.com/blog/best-corporate-tax-software (16 answers)
- https://tax.thomsonreuters.com/blog/corporate-tax-provision-software (15 answers)

## Warned against

- Excel: 6 of 6 labels negative. "Spreadsheets (e.g., Excel) as Primary Tools - Why avoid/caution: Excel offers flexibility but introduces high risks for large-scale operations" (Grok 4.1 Fast, negative prompt)
- Longview Tax: 6 of 29 labels negative. ""Legacy Tools with Stale Architecture (e.g., Longview Tax)" ... "The risk of inaccuracies and lack of auditability makes them a poor choice for large enterprises"" (Muse Glimmer 30B, negative prompt)
- Bloomberg Tax Provision: 5 of 36 labels negative. "Because that expansion is recent, test its coverage against your actual jurisdictions and use cases." (GPT-6 Luna, comparative prompt)
- Avalara: 5 of 12 labels negative. "These are *not* income tax return preparation tools." (DeepSeek V4 Flash, paraphrase prompt)

## Movement since September 2026

Floor: 10 points of share, measured on the calibration repeat.
Same leader: Thomson Reuters ONESOURCE Tax Provision at 44%.

- Thomson Reuters ONESOURCE Tax Provision: 64% to 44%, −19. Cleared the floor by 9 points · rank 1 of 88, unchanged.
- CSC Corptax: 5% to 12%, +7. Inside the floor by 3 points · rank 2 of 88, unchanged.
- Bloomberg Tax Provision: 2% to 5%, +2. Inside the floor by 8 points · rank 6 → 4 of 88.
- Wolters Kluwer CCH Tagetik Tax Provision: 2% to 5%, +2. Inside the floor by 8 points · rank 7 → 5 of 88.
- Workiva Tax and Provision: 0% to 2%, +2. Inside the floor by 8 points · rank 15 → 9 of 88.
- Avalara: 0% to 2%, +2. Inside the floor by 8 points · rank 45 → 16 of 88.
- Sovos Tax Provision: 5% to 2%, −2. Inside the floor by 8 points · rank 3 → 6 of 88.
- Longview Tax: 2% to 2%, ±0. Inside the floor by 10 points · rank 8 → 7 of 88.
- Vertex: 2% to 2%, ±0. Inside the floor by 10 points · rank 9 → 8 of 88.
- Oracle Tax Reporting: 0% to 0%, ±0. Inside the floor by 10 points · rank 14 → 17 of 88.

## Record

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