# BILL vs Xero: which do AI models recommend for invoicing software, September 2026

Finance AI Recommendation Index, September 2026 Edition, Invoicing software. Two of twelve models named BILL first on the direct prompt; zero named Xero. Page: https://finance-ai-index.com/receivables/invoicing-software/bill-vs-xero/

| | First-choice share | Rank | Negative rate | Labels | Models naming it |
|---|---|---|---|---|---|
| BILL | 14% | #3 of 10 | 4% | 26 | 12 of 12 |
| Xero | 2% | #6 of 10 | 0% | 26 | 12 of 12 |

## The direct prompt, model by model

- Grok 4.1 Fast: bill first (first choices: BILL) (alternatives: Chargebee, NetSuite, QuickBooks, Xero)
- MiniMax M2.5: bill first (first choices: BILL) (alternatives: Stampli, Tipalti)
- Claude Haiku 4.5: neither first, one named (first choices: Sage Intacct) (alternatives: BILL, DealHub AI, Younium)
- GPT-5.4 mini: neither first, one named (first choices: NetSuite SuiteBilling) (alternatives: BILL, Sage Intacct)
- Gemini 3.5 Flash: neither first, one named (first choices: Versapay) (alternatives: BILL, Billtrust, Chargebee, Invoiced, Lago, Orb, Quadient AR)
- Perplexity Sonar: neither first, one named (first choices: Invoiced) (alternatives: BILL, NetSuite, QuickBooks)
- Mistral Small: neither first, one named (first choices: Invoiced, SAP) (alternatives: AvidXchange, BILL, Tipalti)
- DeepSeek V4 Flash: neither first, one named (first choices: Billtrust, Invoiced) (alternatives: BILL, Chargebee, HighRadius, Quadient AR, Sage Intacct, Tipalti, Versapay)
- Qwen 3.7 Flash: neither first, one named (first choices: Billforward) (alternatives: BILL, ChargeOver, NetSuite SuiteBilling, Vendormedia)
- Kimi K2: neither first, one named (first choices: HighRadius) (alternatives: BILL, Billtrust, Invoiced, Versapay)
- Llama 4 Maverick: neither named
- GLM 4.7 FlashX: neither named (first choices: Invoiced) (alternatives: Chargebee, QuickBooks, Zoho Invoice)

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.