Fiduciary
A fiduciary is a person or organization that makes financial decisions on behalf of another party who is legally obligated to act in their client's best interests.
Source: Investopedia
Fee-Only
A fee-only financial planner is paid directly by clients for their services, be it a flat fee, hourly rate or a percentage of assets under management. The latter is typically around 1% of a client’s portfolio’s value each year. Their fee-only pay structure means they do not receive commissions or other payments from the providers of financial products they recommend to clients.
Fee-only financial advisors act as a “fiduciary,” a term you may hear thrown around; it means they are obligated to put their clients’ interests first. Ask if your financial planner is a registered investment advisor or a certified financial planner — both types are fiduciaries. This is an important consideration when choosing an advisor.
Source: NerdWallet
Fee-Based
A fee-based financial planner gets paid by the client but also via other sources, such as commissions from financial products that clients purchase. This can set up a conflict of interest, as the advisor charges you for advice while steering you toward investment products from which the advisor profits.
Source: NerdWallet
Section 3(21)
A 3(21) fiduciary is a paid financial advisor who recommends specific investments or assets to a 401(k) plan. Their advice can take many forms, from trading individual stocks, funds and bonds to recommending an overall strategy that the retirement portfolio should take.
Source: SmartAsset
Section 3(38)
A 3(38) fiduciary, sometimes known as an ERISA 3(38) fiduciary or a 3(38) investment manager, is a financial professional who manages the portfolio of a 401(k) account.
Source: SmartAsset