# Corporate tax provision: 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 a mid-market B2B company. Page: https://finance-ai-index.com/tax/corporate-tax-provision/

**Standing:** Thomson Reuters ONESOURCE Tax Provision leads with 21% of first choices; verdict contested. 53 first choices across the direct, paraphrase, budget and scale prompts.

## First-choice share

| # | Product | Share | Negative rate | Labels |
|---|---|---|---|---|
| 1 | Thomson Reuters ONESOURCE Tax Provision | 21% | 39% | 57 |
| 2 | Bloomberg Tax Provision | 19% | 19% | 52 |
| 3 | TaxAct Business | 13% | 0% | 10 |
| 4 | Longview Tax | 4% | 29% | 31 |
| 5 | Vertex | 4% | 10% | 10 |
| 6 | Sovos Tax Provision | 2% | 0% | 16 |
| 7 | Oracle Tax Reporting | 0% | 9% | 11 |
| 8 | Avalara | 0% | 27% | 11 |
| 9 | CSC Corptax | 0% | 42% | 26 |

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

- Claude Haiku 4.5: Bloomberg Tax Provision; alternatives Longview Tax, Thomson Reuters ONESOURCE Tax Provision
- GPT-5.4 mini: Bloomberg Tax Provision, Longview Tax
- Gemini 3.5 Flash: Bloomberg Tax Provision; alternatives Exactera Tax Provision, OneStream, Vena Solutions
- Perplexity Sonar: Thomson Reuters ONESOURCE Tax Provision; alternatives Bloomberg Tax Provision, Longview Tax, Vertex Tax Accounting, Vertex Tax Provision
- Grok 4.1 Fast: Thomson Reuters ONESOURCE Tax Provision, Vertex Corporate Tax; alternatives Bloomberg Tax Provision, Sovos Tax Provision
- Mistral Small: Bloomberg Tax Provision; alternatives Oracle Tax Reporting
- DeepSeek V4 Flash: Bloomberg Tax Provision; alternatives TaxPoint, Thomson Reuters ONESOURCE Tax Provision, Vertex Tax Accounting
- Llama 4 Maverick: no first choice
- Qwen 3.7 Flash: TaxSeries; alternatives Bloomberg Tax Provision, OneStream Tax Provision, Sovos Tax Provision
- Kimi K2: Thomson Reuters ONESOURCE Tax Provision; alternatives Bloomberg Tax Provision, Vertex Tax Accounting
- GLM 4.7 FlashX: Thomson Reuters ONESOURCE Tax Provision; alternatives CCH Axcess Tax, Vertex Tax Accounting
- MiniMax M2.5: Bloomberg Tax Provision, Vertex Tax Accounting; alternatives Oracle Tax Reporting, Thomson Reuters ONESOURCE Tax Provision
- GPT-6 Luna: Thomson Reuters ONESOURCE Tax Provision; alternatives CSC Corptax
- Muse Glimmer 30B: Thomson Reuters ONESOURCE Tax Provision; alternatives Bloomberg Tax Provision, OneStream Tax Provision, Vertex Tax Accounting

## Sources the answers cite

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

- tax.thomsonreuters.com: 44 answers, 96 citations
- worldmetrics.org: 44 answers, 90 citations
- zipdo.co: 40 answers, 86 citations
- gitnux.org: 32 answers, 57 citations
- pro.bloombergtax.com: 25 answers, 72 citations
- theaccountingclub.net: 24 answers, 24 citations
- itechguides.com: 20 answers, 31 citations
- finance-ai-index.com: 19 answers, 28 citations

Pages named in the most answers:

- https://theaccountingclub.net/best-corporate-tax-software (24 answers)
- https://gitnux.org/best/tax-provision-software (22 answers)
- https://tax.thomsonreuters.com/en/tax-accounting/tax-software-for-larger-businesses (22 answers)
- https://zipdo.co/best/corporate-tax-provision-software (22 answers)
- https://pickmysoft.com/blog/best-corporate-tax-software (19 answers)
- https://zipdo.co/best/tax-provision-software (19 answers)
- https://worldmetrics.org/best/corporate-tax-software (17 answers)
- https://zipdo.co/best/corp-tax-software (17 answers)
- https://pro.bloombergtax.com/insights/tax-solutions/buyers-guide-how-to-find-the-right-tax-provision-software (16 answers)
- https://cdn.ymaws.com/www.taxact.org/resource/resmgr/2024_conference/bloomberg_tax.pdf (16 answers)

## Warned against

- Thomson Reuters ONESOURCE Tax Provision: 22 of 57 labels negative. "explicitly says to avoid or be cautious about Longview, ONESOURCE, Workiva, Oracle Tax Reporting, and Corptax" (Perplexity Sonar, negative prompt)
- Bloomberg Tax Provision: 10 of 52 labels negative. ""Avoid Bloomberg Tax Provision and Thomson Reuters ONESOURCE unless you have a large staff and a budget exceeding $25k–$50k/year."" (Muse Glimmer 30B, negative prompt)
- CSC Corptax: 11 of 26 labels negative. "explicitly says to avoid or be cautious about Longview, ONESOURCE, Workiva, Oracle Tax Reporting, and Corptax" (Perplexity Sonar, negative prompt)
- Longview Tax: 9 of 31 labels negative. "one source explicitly says to avoid or be cautious about Longview, ONESOURCE, Workiva, Oracle Tax Reporting, and Corptax in certain budget/fit contexts" (Perplexity Sonar, negative prompt)

## Movement since September 2026

Floor: 10 points of share, measured on the calibration repeat.
New leader: Thomson Reuters ONESOURCE Tax Provision (36%) to Bloomberg Tax Provision (22%). Margin 4 points, within noise.

- Thomson Reuters ONESOURCE Tax Provision: 36% to 18%, −18. Cleared the floor by 8 points · rank 1 → 2 of 94.
- Bloomberg Tax Provision: 10% to 22%, +13. Cleared the floor by 3 points · rank 2 → 1 of 94.
- Avalara: 7% to 0%, −7. Inside the floor by 3 points · rank 5 → 24 of 94.
- Longview Tax: 7% to 2%, −5. Inside the floor by 5 points · rank 3 → 10 of 94.
- Vertex: 2% to 4%, +2. Inside the floor by 8 points · rank 16 → 5 of 94.
- Sovos Tax Provision: 0% to 0%, ±0. Inside the floor by 10 points · rank 18 → 17 of 94.
- Workiva Tax and Provision: 0% to 0%, ±0. Inside the floor by 10 points · rank 21 → 22 of 94.
- CSC Corptax: 0% to 0%, ±0. Inside the floor by 10 points · rank 22 → 90 of 94.

## 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.