Issue 053 - Federal budget - Cost and budget
What would a $5,000 payment to every U.S. adult cost?
President Trump proposed giving $5,000 to every adult U.S. citizen if Republicans retain control of Congress in the 2026 midterm elections. The proposal would require congressional approval, and details about eligibility and funding remain unclear.
The problem
Estimate the total federal cost of making a $5,000 payment to every adult U.S. citizen.
Then estimate how much time it takes the federal government to collect an equivalent amount in total tax and other federal revenue.
You will need to estimate the U.S. population, what fraction of the population is adult, what fraction of adults are U.S. citizens, and how much revenue the federal government collects in a typical year.
The political arguments for or against the proposal are separate from the calculation. The purpose here is to establish the scale of the proposed expenditure.
Because Fermi problems target an order of magnitude, I normally use no more than two significant digits and write most calculations in scientific notation; the Fermi reference explains both conventions.
Before checking sources
Matt's first pass
It would have been much easier to solve this one if I maintained some sort of memory peg about federal tax revenues.
I started by figuring out how much would need to be paid. Assuming there is an even distribution of people across all ages, which there is not, and that the most densely populated age buckets are 0 to 80 years old, about 78% of all U.S. citizens would be in the adult age buckets.
Starting with 330 million Americans, that gives about 260 million adult citizens. A $5,000 payment to each of those individuals is $1.3 trillion. Immediately, this feels like an enormous number.
adult citizens ~= 3.3 x 10^8 people x 0.78
~= 2.6 x 10^8
total payment cost
~= 2.6 x 10^8 people x $5 x 10^3/person
~= $1.3 x 10^12My intuitions are that the average American makes an income of about $55,000 per year. Looking back, I think that is more like the household number than the working-American number. I also think the average effective federal tax rate is something like 20%.
If I assume about 200 million Americans are working, excluding unemployed adults and retired adults, and there is about $11,000 of tax revenue from each income earner on average, then that is about $2.2 trillion in federal tax revenue from income. I think this accounts for about half of all federal tax revenue, so I am estimating federal government revenue at about $4.4 trillion annually.
income-tax-like revenue
~= 2 x 10^8 workers x $1.1 x 10^4/worker
~= $2.2 x 10^12/year
total federal revenue
~= $2.2 x 10^12 / 0.5
~= $4.4 x 10^12/yearIf that revenue is received at a constant rate over the year, which it is not, then a $1.3 trillion payout reflects about 3.5 months of federal tax revenue, or more than a quarter of annual federal tax revenue.
revenue-time equivalent
~= $1.3 x 10^12 / $4.4 x 10^12 per year
~= 0.30 years
~= 3.5 monthsAt this scale, the funding mechanism becomes the central follow-up question.
Calibration note
This page is published as an unscored scale check because the hook is an election-conditioned proposed policy. It is excluded from Matt's numerical Calibration Score averages, but the estimate is still compared with sourced reference numbers below.
Grounding facts
AP reports that the proposal would require congressional approval and could cost more than $1 trillion. Its accompanying estimate uses 245,275,126 adult U.S. citizens and a $5,000 payment, producing an estimated total near $1.23 trillion.
CBO's February 2026 outlook projected federal revenues of about $5.6 trillion in fiscal year 2026. CBO's September 2026 monthly review estimated that receipts totaled $4.845 trillion during the first 11 months of FY2026.
Those revenue figures imply a federal-revenue pace around $15 billion per day, or roughly $440 billion to $470 billion per month, depending on whether you use annual projections or the first 11 months of actual and preliminary receipts.
After checking sources
Check and recalibrate
Start with the adult-citizen estimate used by AP's source table:
total payment cost
~= 2.45 x 10^8 adult citizens x $5 x 10^3/person
~= $1.225 x 10^12
~= $1.2 trillionThen convert federal annual revenue into a daily pace:
federal revenue per day
~= $5.6 x 10^12/year / 365
~= $1.5 x 10^10/day
~= $15 billion/dayNow divide the payout cost by that daily revenue pace:
revenue-time equivalent
~= $1.225 x 10^12 / $1.5 x 10^10/day
~= 8.0 x 10^1 days
~= 80 daysThe best Fermi answer is therefore about $1.2 trillion, equivalent to roughly 80 days of total federal revenue, or about 2.5 to 3 months.
Using the first 11 months of FY2026 receipts gives nearly the same scale: $4.845 trillion / 11 months ~= $440 billion/month, and $1.225 trillion / $440 billion/month ~= 2.8 months.
Matt's total payout estimate was essentially right. The revenue-time estimate was somewhat high because the federal revenue peg was low, but the result still landed in the right order of magnitude: months of federal revenue, not days and not a full year.
Post-check reflection
Matt's reflection
Looks like my intuitions and estimates were closer than I expected. The percentage of Americans who are age 18 or older was pretty much dead-on, and my calculation for the total payment amount was essentially correct as well.
I underestimated total federal tax revenues by about $1 trillion, but I was remarkably close there. My main errors were running the calculation with a low average household earning and a low worker count, though not all workers are full-time. The tax rate I used was probably a bit high, but that corrected for the low-ball estimates.
My final answer was reasonably close. On its face, this understanding of scope makes the funding mechanism the central unresolved question, since details about eligibility and funding have not been specified.
Recommended memory peg
For U.S. federal budget problems, remember: the adult U.S. citizen population is roughly 2.5 x 10^8, and annual federal revenue is roughly $5.5 x 10^12, or about $1.5 x 10^10 per day. A $1 trillion federal cost is therefore on the order of two months of all federal revenue.
Reader results
Bars show how submitted estimates sort into the answer choices from the gut-check prompt.