Fine-Tuning vs RAG: Which One Do You Actually Need?
June 17, 2026 · 9 min read
Nine times out of ten the answer is retrieval, not fine-tuning.
Use RAG for facts
Anything that changes — docs, prices, policies — belongs in retrieval, not weights.
Use fine-tuning for behavior
Consistent format, tone, or a narrow classification task justify training.
Cost and maintenance
Fine-tunes go stale and must be re-run; retrieval indexes update continuously.
Combining both
A small fine-tune for style plus retrieval for facts is a strong production pattern.