How Is Poverty Measured in the United States: OPM, SPM, and Guidelines

Poverty in the United States is measured three different ways, and each answers a different question. The Census Bureau publishes the Official Poverty Measure (OPM), the long-running statistical yardstick built on 1960s food-cost math and updated for inflation. It also publishes the Supplemental Poverty Measure (SPM), a newer figure that factors in government benefits, taxes, work expenses, and where you live. Separately, the Department of Health and Human Services issues the federal poverty guidelines each January, and those are the numbers Medicaid, SNAP, and other programs actually use to decide who qualifies.{¹}

The Official Poverty Measure

The OPM is the number behind almost every historical statistic you have seen about the U.S. poverty rate. Its logic traces back to economist Mollie Orshansky at the Social Security Administration, who in the early 1960s took the cost of the Agriculture Department’s cheapest food plan and multiplied it by three, on the finding that families then spent about a third of their after-tax income on food.{²} Each year the Census Bureau adjusts those thresholds by the Consumer Price Index for All Urban Consumers (CPI-U), but the underlying formula has not changed.{³}

The OPM looks only at gross pre-tax cash income: wages, Social Security, unemployment, interest, dividends, pensions, workers’ compensation, alimony, and similar cash sources. It ignores non-cash benefits like housing vouchers, food assistance, and employer health insurance, and it ignores taxes and tax credits entirely because the calculation happens before taxes.{¹} The Bureau totals the cash income of everyone in a family and compares it against a single national threshold for that family’s size and composition.

That narrow focus gives researchers a consistent yardstick reaching back decades, but it has real limits. American spending has shifted since the 1950s: families now spend less than 15 percent of their income on food, while housing, child care, and health care take a much bigger share. Because the OPM is essentially the old food-plan cost adjusted for general inflation, it does not reflect what families actually need to spend today. It also cannot show whether programs like SNAP or the Earned Income Tax Credit are reducing hardship, because it does not count them.

The Supplemental Poverty Measure

The Census Bureau began publishing the SPM in 2011 to address those gaps. Its thresholds are anchored to what families actually spend on food, clothing, shelter, and utilities, calculated by the Bureau of Labor Statistics from a five-year moving average of the Consumer Expenditure Survey.{⁴}

The income side is broader too. The SPM starts with cash income, then adds the value of non-cash benefits like SNAP, WIC, the National School Lunch Program, housing subsidies, and energy assistance. It then subtracts federal and state income taxes, payroll taxes, out-of-pocket medical costs, child care, work-related transportation, and child support paid.{⁵} Tax credits like the EITC count as income, so the SPM can actually show whether they lift a family above the poverty line.

The SPM also adjusts for geography. Because housing is close to half of the SPM threshold, the Census Bureau varies the shelter-and-utilities portion using median gross rent for two-bedroom units in each metropolitan area and state. A family in an expensive metro area faces a higher SPM threshold than the same family in a rural area with cheap rent.{⁴} The OPM applies one national threshold no matter where you live.

Neither measure is right in an absolute sense. The OPM gives a clean long-term trend line. The SPM gives a fuller picture of how people are actually living, including whether public programs are keeping them out of poverty or whether medical bills are pushing them into it.

Who Counts as a Household

The two measures also group people differently, and that shifts who ends up counted as poor. Under the OPM, a “family” is two or more people living together who are related by birth, marriage, or adoption; their combined income determines everyone’s poverty status. Someone living alone or with unrelated roommates is measured on their own income.{¹}

The SPM uses a broader “resource unit” that groups cohabiting partners and their children together even when the partners are not married. An unmarried couple living together is two separate units under the OPM but one combined unit under the SPM. That single change moves millions of households and can push poverty rates in either direction depending on whether the partner’s income helps or hurts.

The Federal Poverty Guidelines

Neither the OPM thresholds nor the SPM figures are what caseworkers check when you apply for benefits. That job belongs to the poverty guidelines, a simplified set of numbers published each January by HHS. Congress authorized them under 42 U.S.C. § 9902(2), which directs HHS to update them annually by the percentage change in the CPI-U.{⁶}

The guidelines appear in the Federal Register and underpin eligibility for Medicaid, SNAP, the Children’s Health Insurance Program, Head Start, the Low Income Home Energy Assistance Program, and the National School Lunch Program, among others.{⁷} Most programs do not use 100% of the guideline as their cutoff. Authorizing statutes or regulations set eligibility at some multiple, such as 130%, 138%, 185%, or 400% of the guidelines, and each program has its own definition of income and its own household rules.

Unlike the OPM’s single national threshold, the guidelines publish separate figures for Alaska and Hawaii to reflect higher living costs there.

2026 Federal Poverty Guidelines

For 2026, the guidelines for the 48 contiguous states and the District of Columbia are:{⁸}

1 person: $15,960
2 people: $21,640
3 people: $27,320
4 people: $33,000
5 people: $38,680
6 people: $44,360
7 people: $50,040
8 people: $55,720

For households larger than eight, add $5,680 per additional person.{⁷}

Alaska’s 2026 guideline is $19,950 for one person and $41,250 for a family of four, with $7,100 added for each person beyond eight. Hawaii falls in between: $18,360 for one person, $37,950 for a family of four, and $6,530 per additional person beyond eight.{⁹}

How Programs Apply the Numbers

The figures above are 100% of the federal poverty level (FPL). Programs set their cutoffs at multiples of that. Medicaid eligibility in states that expanded coverage under the Affordable Care Act reaches 138% of FPL, which works out to roughly $45,540 for a family of four in the contiguous states in 2026. SNAP generally uses 130% of FPL for gross income eligibility. ACA premium tax credits have historically been available up to 400% of FPL, though current rules depend on the legislation in effect.

These percentage cutoffs produce what is often called the benefit cliff. A small raise can push a household just past an eligibility threshold and cause a sudden loss of benefits large enough that the family comes out worse off than before the raise. That dynamic discourages some workers from taking on more hours, and several states have tried gradual phase-outs instead of hard cutoffs.

Thresholds vs. Guidelines

People use “poverty threshold” and “poverty guideline” interchangeably, but they are different documents produced by different agencies for different purposes. The thresholds are the detailed Census Bureau statistical figures, laid out in a matrix that varies by family size, number of children, and whether the householder is over or under 65. Researchers use them to calculate the national poverty rate. The guidelines are the simplified HHS version, varying only by household size and by whether you live in the contiguous states, Alaska, or Hawaii. Agencies and nonprofits use the guidelines for eligibility. The two sets of numbers differ by a few hundred dollars for any given family size because HHS rounds and simplifies for administrative use. If you are applying for benefits, the guidelines are the numbers that decide your case. If you are reading a Census report about the poverty rate, the thresholds produced that figure.

1
United States Census Bureau. How the Census Bureau Measures Poverty
2
Office of the Assistant Secretary for Planning and Evaluation (ASPE). History of Poverty Thresholds
3
Census Bureau. The Development of the Orshansky Poverty Thresholds and Their Subsequent History as the Official U.S. Poverty Measure
4
United States Census Bureau. What’s the Difference Between the Supplemental and Official Poverty Measures?
5
United States Census Bureau. Supplemental Poverty Measure Rose in 2023 for Second Consecutive Year
6
Office of the Law Revision Counsel. 42 USC 9902 – Definitions
7
Federal Register. Annual Update of the HHS Poverty Guidelines
8
U.S. Department of Health and Human Services, Office of the Assistant Secretary for Planning and Evaluation (ASPE). 2026 Poverty Guidelines: 48 Contiguous States
9
U.S. Department of Health and Human Services, Office of the Assistant Secretary for Planning and Evaluation (ASPE). 2026 Poverty Guidelines: Alaska and Hawaii