FinRAG-12B: A Production-Validated Recipe for Grounded Question Answering in Banking

Denys Katerenchuk, Pablo Duboue, Keelan Evanini


Abstract
Large language models (LLMs) are rapidly being adopted across various domains. However, their adoption in banking industry faces resistance due to demands for high accuracy, regulatory compliance, and the need for verifiable and grounded responses. We present a unified, data-efficient framework for training grounded domain-specific LLMs that optimizes answer quality, citation grounding, and calibrated refusal under real-world deployment constraints. First, we describe a data generation pipeline that combines LLM-as-a-Judge filtering, citation annotation, and curriculum learning with only 143M tokens. The resulting 12B model achieves high answer quality outperforming GPT-4.1 on citation grounding, with a modest citation tradeoff versus the untuned base. Second, we propose a calibrated refusal mechanism: training on 22% unanswerable examples yield a 12% “I don’t know” rate, substantially improving over the base model’s unsafe 4.3% rate while avoiding GPT-4.1’s over-refusal (20.2%). Third, we present an end-to-end methodology spanning from data curation to quantized serving. The system is deployed at 40+ financial institutions, achieving a 7.1percentage point improvement in query resolution (p < 0.001). Additionally, the model delivers 3–5x faster responses at 20–50x lower cost compared to GPT-4.1.
Anthology ID:
2026.acl-industry.92
Volume:
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (ACL 2026)
Month:
July
Year:
2026
Address:
San Diego, California, USA
Editors:
Yunyao Li, Georg Rehm, Mei Tu
Venue:
ACL
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
1317–1328
Language:
URL:
https://preview.aclanthology.org/ingest-acl/2026.acl-industry.92/
DOI:
Bibkey:
Cite (ACL):
Denys Katerenchuk, Pablo Duboue, and Keelan Evanini. 2026. FinRAG-12B: A Production-Validated Recipe for Grounded Question Answering in Banking. In Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (ACL 2026), pages 1317–1328, San Diego, California, USA. Association for Computational Linguistics.
Cite (Informal):
FinRAG-12B: A Production-Validated Recipe for Grounded Question Answering in Banking (Katerenchuk et al., ACL 2026)
Copy Citation:
PDF:
https://preview.aclanthology.org/ingest-acl/2026.acl-industry.92.pdf