Regulation Best Interest is the SEC rule (effective 2020) requiring broker-dealers to act in a retail customer's best interest when recommending securities transactions or investment strategies, raising the bar above the prior 'suitability' standard without imposing a full fiduciary duty equivalent to that of Registered Investment Advisers.
Why It Matters
Reg BI reshaped how brokerage firms document and defend investment recommendations — it requires firms to address conflicts of interest (proprietary products, differential compensation) that suitability alone never forced them to confront, and it remains the dividing line in the long-running industry debate over whether brokers should simply be held to the same fiduciary standard as RIAs.
How It Works in Practice
- 1Disclosure obligation: firms must disclose material facts about the recommendation and any conflicts of interest
- 2Care obligation: the recommendation must reflect reasonable diligence to understand the risks, rewards, and costs, and be in the customer's best interest given their investment profile
- 3Conflict of interest obligation: firms must establish policies to identify and mitigate (not merely disclose) certain conflicts, including eliminating sales contests tied to specific products
- 4Compliance obligation: firms must maintain written policies reasonably designed to achieve compliance with the rule
Common Pitfalls
Reg BI applies to specific recommendations, not to an ongoing advisory relationship the way fiduciary duty does under the Investment Advisers Act — the practical difference between the two standards is subtle and frequently misunderstood by retail clients and even some practitioners
"Best interest" under Reg BI is judged based on the information available at the time of the recommendation, not with the benefit of hindsight if the recommendation later underperforms
State-level fiduciary rules (some states have enacted their own, stricter standards for broker-dealers) can layer additional requirements on top of the federal Reg BI baseline