What Is 30-day yield

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Last updated: April 15, 2026

Quick Answer: The 30-day yield is a standardized measure of a fund's income over the past 30 days, expressed as an annualized percentage. It is calculated by the SEC and reported monthly to help investors compare bond and money market funds.

Key Facts

The 30-day yield is calculated using data from the past 30 days and annualized for comparison purposes
It was standardized by the SEC in 1988 to ensure consistent reporting across funds
Money market funds and bond ETFs commonly report 30-day yields
A 30-day yield of 4.2% means the fund earned that rate over the past month, projected annually
Unlike dividend yield, the 30-day yield includes capital gains distributions and interest payments

Overview

The 30-day yield is a financial metric used primarily for mutual funds, bond funds, and money market funds to express recent income generation. It provides investors with a standardized way to compare the performance of income-producing funds over a recent, consistent period.

This figure is especially useful in volatile interest rate environments, where past annual yields may not reflect current returns. By focusing on the most recent month, the 30-day yield offers a more up-to-date snapshot than trailing 12-month yields.

SEC-mandated calculation: The 30-day yield is calculated using a formula required by the U.S. Securities and Exchange Commission, ensuring consistency across fund disclosures.
Annualized projection: Although based on 30 days of data, the yield is annualized to help investors understand what full-year returns might look like if current performance continues.
Includes distributions: The calculation accounts for dividends, interest payments, and capital gains distributions made by the fund during the period.
Net of expenses: Fund fees and operating expenses are deducted before computing the yield, giving a more accurate picture of investor returns.
Monthly reporting: Funds typically report the 30-day yield each month, allowing investors to track changes in real time as interest rates and market conditions shift.

How It Works

The 30-day yield uses a specific formula defined by the SEC to standardize reporting across all regulated funds. This allows for apples-to-apples comparisons between similar funds, especially in the bond and money market sectors.

Term: The 30-day period refers to the most recent 30 calendar days for which data is available. This short window makes the yield sensitive to recent market changes, such as Federal Reserve rate adjustments.
Formula basis: The yield is calculated by taking the sum of daily distributions over 30 days, subtracting any fees, and dividing by the maximum offering price per share on the last day of the period.
Annualization: The 30-day income is multiplied by 12 to project a full year’s return, assuming performance remains constant—a key point when rates are changing rapidly.
Applicable funds: The metric is most commonly used for money market funds, municipal bond funds, and taxable bond ETFs, where income generation is a primary goal.
Public disclosure: The 30-day yield must appear in fund fact sheets, prospectuses, and online performance tables, making it easily accessible to retail investors.
Regulatory consistency: Since the SEC standardized the calculation in 1988, all funds must use the same methodology, reducing the risk of misleading or inflated yield claims.

Comparison at a Glance

The following table compares the 30-day yield to other common yield metrics used in investing:

Metric	Time Period	Use Case	Standardized?
30-day yield	Last 30 days (annualized)	Money market and bond funds	Yes (SEC)
Trailing 12-month yield	Most recent 12 months	Dividend-paying stocks and equity funds	No
Distribution yield	Most recent distribution	REITs and closed-end funds	No
1-year yield	Historical 12 months	Comparative performance	Sometimes
Forward yield	Projected next 12 months	Stocks and ETFs	No

While the 30-day yield offers timeliness and regulatory consistency, other metrics like the trailing 12-month yield may better reflect long-term performance. Investors should consider multiple yield types depending on their time horizon and risk tolerance. The 30-day yield is best for assessing current income potential, especially in interest-rate-sensitive funds.

Why It Matters

Understanding the 30-day yield is essential for income-focused investors who rely on regular payouts from their portfolios. It provides a clear, comparable metric that reflects recent fund performance without the lag of longer-term averages.

Interest rate sensitivity: When the Federal Reserve changes rates, the 30-day yield quickly reflects those shifts, helping investors adjust allocations promptly.
Portfolio income planning: Retirees and fixed-income investors use the 30-day yield to estimate monthly or quarterly cash flow from bond holdings.
Performance benchmarking: Investors can compare funds with similar objectives using the 30-day yield to identify better-performing options.
Transparency: The SEC standardization reduces the risk of misleading yield claims, increasing trust in reported figures.
Market condition indicator: A rising 30-day yield across multiple funds may signal tightening monetary policy or improving credit conditions.
Short-term decision making: Traders and tactical asset allocators use the metric to time entries and exits in fixed-income markets.

While not a predictor of future performance, the 30-day yield remains a vital tool for assessing current income potential in regulated funds. When combined with other metrics, it helps investors make more informed, data-driven decisions.