# How the Census Apportions Congress The decennial pipeline that sets everything downstream: a headcount taken on one day in April, a formula with no discretion in it, a presidential transmittal that courts have held they cannot review, and a certification to fifty governors that starts every redistricting fight in the country. This map covers the stretch from *enumeration* to *seats*. [[How a Redistricting Map Is Drawn and Challenged]] picks up where this one ends, and [[Congressional Apportionment Mathematics]] goes deeper on the formula itself — the paradoxes that killed the earlier methods and the impossibility result underneath all of them. This map deliberately does not restate that math; it maps the pipeline around it. The reason to read it as machinery rather than arithmetic is that the arithmetic is the one stage nobody can touch. Every fight over apportionment is a fight over an *input* — who gets counted, where they get counted, whether they get counted at all — because the formula that turns those inputs into 435 seats is fixed by statute and runs the same way regardless of who is in office. That is also why the live 2025–26 conflict is not about the 2030 count. It is about two statutory reporting deadlines that fall in **2027 and 2028**, before a single form is printed. Time-slice: law and litigation as of **September 1, 2026**; the dates in the fence are the 2030 cycle. No officeholders are named inside the chart — the pipeline does not change with who holds the seats. > [!note] How to read this chart > `──▶` = the main path · `└─▶` = a branch, attack surface, or workaround · `◇` = a decision point · `★` = a legally operative act · `✕` = a route that is closed or barred. Everything inside the fence is plain text; wikilinks live in the prose, Notes, and See also. Bracketed dates are the actual 2030-cycle dates the statutory formulas produce. Bracketed `[live]` marks something in motion as of the build date. ``` HOW THE CENSUS APPORTIONS CONGRESS — ENUMERATION TO SEATS │ Legend: ──▶ main path └─▶ branch/attack surface ◇ decision ★ operative ✕ closed │ Time-slice: law as of Sept 1, 2026 · dates shown are the 2030 cycle │ ■ 0. THE FLOOR — TWO NUMBERS THAT DO NOT MOVE, ONE THAT DOES │ Art. I, § 2, cl. 3 — an "actual Enumeration" every ten years, "in such Manner as │ they shall by Law direct." THE POWER IS CONGRESS'S. Congress handed the count to │ the Secretary of Commerce by statute (13 U.S.C. § 141(a)). The President appears │ exactly once in this pipeline, at step 5, as a courier. │ ├─ 14th Am., § 2 — seats apportioned "counting the whole number of persons in │ │ each State." Superseded the three-fifths clause. The only textual carve-out, │ │ "Indians not taxed," has had no practical effect for a century. │ │ │ ├─ ★ FIXED #1 — 435 SEATS. This is a STATUTE, not the Constitution. Capped at │ │ 435 by the Apportionment Act of 1911 and made permanent — the size frozen and │ │ reapportionment made automatic — by the Permanent Apportionment Act of 1929. │ │ A simple majority of Congress could change it tomorrow. │ ├─ ★ FIXED #2 — ONE SEAT PER STATE MINIMUM. This one IS constitutional. │ ├─ ✕ NOT IN THE POOL — D.C., Puerto Rico, and the territories. No voting seats, │ │ so their residents are counted but not apportioned. (D.C. gets 3 electoral │ │ votes under the 23rd Am.; that is a separate mechanism.) │ └─ ◆ WHAT MOVES — which states gain and lose. Nothing else in this block does. │ ├─◆ 1. WHO COUNTS, AND WHERE — the residence rule does more work than any other step │ │ APPORTIONMENT POPULATION = resident population + overseas federal employees │ │ allocated back to a home state. That sum, and only that sum, enters the formula. │ ├─ ★ USUAL RESIDENCE — where a person lives and sleeps most of the time. Not │ │ citizenship. Not voter eligibility. Not age. Newborns count; noncitizens count. │ ├─ GROUP QUARTERS — counted where the facility is: │ │ ├─ prisons ...... at the prison, not the last home address │ │ │ (the origin of the prison-gerrymandering problem downstream) │ │ ├─ college dorms at the school │ │ └─ nursing homes · shelters · barracks ... at the facility │ ├─ OVERSEAS — military and civilian federal employees and dependents living with │ │ them, allocated to a home state from employer administrative records. Private │ │ citizens living abroad are NOT counted at all. │ │ │ └─▶ ◇ ATTACK SURFACE #1 — CHANGE WHO IS IN THE BASE │ ├─ 2019: an EO directed agencies to build citizenship data for the 2020 count │ ├─ Jul 2020: a presidential memo ordered persons without lawful status │ │ excluded from the apportionment base — the first such attempt ever │ ├─ Jan 2021: EO 13986 revoked both and restored the whole-persons rule │ ├─ Jan 20, 2025: EO 14148 revoked EO 13986 [live — no replacement policy │ │ has been issued, so the operative rule is the statute, not an EO] │ └─ ✕ NEVER ADJUDICATED ON THE MERITS. The Court blocked the 2020 citizenship │ QUESTION as pretextual but has never ruled on whether the President may │ exclude anyone from the apportionment BASE. That door is untested, not shut. │ ├─◆ 2. THE QUESTION CLOCK — the deadlines that decide 2030, four years early │ │ 13 U.S.C. § 141(f). Whatever is on the form must clear Congress first, in writing. │ ├─ ★ SUBJECTS REPORT — due 3 years before the census date ....... by Apr 1, 2027 │ ├─ ★ QUESTIONS REPORT — due 2 years before the census date ...... by Apr 1, 2028 │ ├─ [live] THIS IS THE REAL 2030 DEADLINE. An immigration-status question that is │ │ not in the subjects report is a question with a statutory problem before it has │ │ a constitutional one. Seven months out as of Sept. 2026. │ └─ ◇ and the reverse: a question reported in 2027 can still be pulled by a later │ administration or by Congress before the forms are printed in 2029 │ ├─◆ 3. THE COUNT ITSELF [census date: Mon Apr 1, 2030] │ ├─ address canvassing ──▶ self-response (internet · phone · paper) │ │ ──▶ NONRESPONSE FOLLOWUP (enumerators in the field) │ │ ──▶ administrative records and imputation for what remains │ ├─ ✕ SAMPLING IS BARRED FOR APPORTIONMENT. 13 U.S.C. § 195 permits statistical │ │ sampling everywhere in Title 13 EXCEPT the apportionment determination, and the │ │ Court so held in 1999. Sampling remains lawful for redistricting data and │ │ funding formulas — the split that makes the apportionment number the least │ │ correctable number the Bureau produces. │ ├─ ✓ IMPUTATION IS NOT SAMPLING. Utah v. Evans (2002) upheld hot-deck imputation │ │ for the counts that fed apportionment — a distinction of a few thousand people │ │ and, that year, one House seat. │ ├─ POST-ENUMERATION SURVEY — measures the differential undercount AFTER the fact. │ │ ★ It never changes the apportionment number. It is a report card, not a fix. │ └─ DISCLOSURE AVOIDANCE — noise injected into PUBLISHED tables to protect │ confidentiality. State apportionment totals are published as enumerated. │ [live: a 2026 Commerce order changed the method; the fight is over the │ granularity of race, ethnicity, and small-area data, not the seat math] │ ├─◆ 4. ★ TABULATION → SECRETARY → PRESIDENT [due Tue Dec 31, 2030] │ │ 13 U.S.C. § 141(b) — the tabulation of total population by state, "as required │ │ for the apportionment," completed within 9 MONTHS of the census date and │ │ reported by the Secretary of Commerce to the President. │ └─ ◆ THIS IS WHERE JUDICIAL REVIEW ATTACHES. The Secretary is an agency head doing │ a statutory act. Everything after this step is much harder to sue over. │ ╞═════════ 5. ★ THE MATH — METHOD OF EQUAL PROPORTIONS (2 U.S.C. § 2a) ══════════════════ │ Adopted 1941, used after every census since 1940. Also called Huntington-Hill. │ The ONLY inputs are the fifty state numbers from step 4. There is no discretion here. │ │ STEP A ──▶ every state gets 1 seat first .......... 50 assigned · 385 remain │ STEP B ──▶ for each state, compute a PRIORITY VALUE for its nth seat: │ priority(n) = state population ÷ √(n × (n−1)) │ (the divisor is the geometric mean of the seat it has and the seat it wants) │ STEP C ──▶ rank every priority value nationwide, largest to smallest │ STEP D ──▶ ★ the top 385 values take the remaining seats. Done. │ │ WHY THE MARGINS ARE THE STORY — 2020 result, for scale: │ ├─ average district after 2020 ........... 761,169 people (up 7.1% from 2010) │ ├─ gained ... TX +2 · CO, FL, MT, NC, OR +1 (7 seats moved) │ ├─ lost ..... CA, IL, MI, NY, OH, PA, WV −1 │ └─ ★ THE 435TH SEAT WENT TO MINNESOTA. NEW YORK MISSED IT BY 89 PEOPLE. │ A differential undercount of one mid-sized apartment block is a seat. │ ├─◆ 6. ★ THE PRESIDENT TRANSMITS [within 1 week of the new session opening — Jan 2031] │ │ 2 U.S.C. § 2a(a) — a statement to Congress showing the whole number of persons │ │ in each state and the number of Representatives each is entitled to. │ ├─ ✕ FRANKLIN v. MASSACHUSETTS (1992) — the President is not an "agency," so the │ │ transmittal is not final agency action reviewable under the APA. The courthouse │ │ door at THIS step is closed; it was open one step earlier. │ └─▶ ◇ THE PRESIDENT TRANSMITS A NUMBER OTHER THAN THE WHOLE NUMBER OF PERSONS │ ├─ tried once, in 2020, by presidential memorandum │ ├─ ✕ Trump v. New York (2020) — vacated as UNRIPE and premature. The Court │ │ never reached whether it may be done. The 2020 count ran late, the │ │ term ended, and the successor revoked the memo. The question survives. │ └─ ⚠ the combination is the structural hazard: an act with no APA review at │ step 6, resting on a question the Court has twice declined to answer │ ├─◆ 7. ★ THE CLERK CERTIFIES TO THE STATES [within 15 days of receipt] │ ├─ 2 U.S.C. § 2a(b) — the Clerk of the House sends each governor the number of │ │ Representatives that state is entitled to. Ministerial. No discretion. │ └─ 2 U.S.C. § 2a(c) — the DEFAULT RULES if a state has not redistricted in time: │ a state that gained seats elects the extra members AT LARGE; a state that │ lost seats elects its whole delegation at large. Rarely reached — but it is │ the reason a state legislature that misses its own deadline still has a map. │ └─◆ 8. ──▶ HANDOFF TO REDISTRICTING ├─ 13 U.S.C. § 141(c) — block-level tabulations (the P.L. 94-171 file) go to each │ governor and redistricting body WITHIN ONE YEAR of the census date [Apr 2031] └─ ──▶ from here the process is fifty separate state processes. See the redistricting map. ╞═════════════════ THE THREE LEVERS — EVERY FIGHT IS ONE OF THESE ════════════════════════ │ ├─◆ LEVER 1 — CHANGE WHO IS COUNTED (attacks step 1) │ ├─ an immigration-status or citizenship question on the form │ ├─ excluding a class of residents from the apportionment base after the count │ └─ ◇ the constitutional hook is the phrase "whole number of persons," and it has │ never been construed by the Court in this posture │ ├─◆ LEVER 2 — CHANGE HOW WELL THEY ARE COUNTED (attacks step 3, and leaves no fingerprints) │ ├─ outreach funding · field-office count · length of the response window · │ │ a question that suppresses response in specific communities │ ├─ ★ THE UNDERCOUNT IS NOT RANDOM. It concentrates in the same populations every │ │ decade, so degrading accuracy has a predictable direction. │ └─ ✕ and there is no correction downstream — sampling is barred at step 3 and the │ post-enumeration survey only measures the error it cannot fix │ └─◆ LEVER 3 — CHANGE THE NUMBER OF SEATS (attacks step 0) ├─ 435 is an ordinary statute. Enlarging the House is the one lever that requires │ no constitutional argument at all — and the one nobody with power wants. ├─ ✕ THE MID-DECADE ROUTE IS CLOSED BY STATUTE. 13 U.S.C. § 141(d) authorizes a │ mid-decade census in years ending in 5 — but § 141(e)(2) says its information │ "shall not be used for apportionment of Representatives in Congress among the │ several States, nor ... in prescribing congressional districts." An off-cycle │ recount can be run. It cannot move a seat without Congress amending that clause. └─ ◇ a bill could do all of this — change the base, the size, or the timing — which is why the live proposals are legislative and not merely executive ╞═════════════════ WHAT IS ACTUALLY IN MOTION — 2025 TO SEPT 2026 ════════════════════════ │ ├─ Jan 20, 2025 .... EO 14148 revokes EO 13986, removing the whole-persons executive policy ├─ Jul 2025 ........ the 2030 operational plan, v1, is published; the 2026 field test is set ├─ Aug 7, 2025 ..... the President posts that he has directed Commerce to begin a "new" │ census excluding people without lawful status, keyed to the 2024 │ election results. No implementing document has followed. ├─ Jan 30, 2026 .... Missouri and three residents sue Commerce and the Bureau in E.D. Mo., │ seeking to void the 2020 method, REDO the 2020 count, and bar │ noncitizens from the 2030 apportionment base ├─ Feb–Apr 2026 .... four sets of intervenors move in on the defense side; the court │ DENIES a three-judge panel (Apr 3) at this stage of the case ├─ Jun 26, 2026 .... ⚠ THE FEDERAL DEFENDANTS MOVE TO STAY THE CASE — the administration │ asks the court to pause a suit seeking the outcome it has demanded ├─ Jul 29, 2026 .... GAO reports to Commerce that 2030 planning and PII protection both │ "warrant timely and focused attention" └─ Aug 2026 ........ Senate CR carries a census funding anomaly (Sec. 120) letting 2030 prep be funded at need under a CR; the House CR carries none [live — unreconciled, and the fiscal year ends Sept 30] ╞═════════════════════════════ FIVE STRUCTURAL FACTS ═════════════════════════════════════ │ │ 1. THE FORMULA IS THE ONLY HONEST STEP, WHICH IS WHY EVERY FIGHT IS UPSTREAM OF IT. │ Steps 5 through 7 have no discretion in them at all. Every contested decision │ happens at steps 1, 2, and 3 — who is in the base, what is on the form, and how │ hard anyone tries to find people. │ │ 2. THE POWER IS CONGRESS'S AND HAS BEEN DELEGATED, NOT SURRENDERED. │ Article I gives the enumeration to Congress "in such Manner as they shall by Law │ direct." Everything the executive does here — the count, the method, the deadlines, │ the ban on sampling — it does because a statute says so, and Congress can rewrite │ any of it by simple majority. │ │ 3. THE APPORTIONMENT NUMBER IS THE LEAST CORRECTABLE NUMBER THE GOVERNMENT PRODUCES. │ Sampling is barred, the post-enumeration survey is diagnostic only, and no statute │ provides for revising an apportionment once transmitted. An error found in 2032 │ is an error the country lives with until 2033. │ │ 4. THE REVIEW WINDOW IS ONE STEP WIDE. │ The Secretary's report is agency action and reviewable. The President's transmittal │ is not (Franklin). The Clerk's certification is ministerial. Anyone who wants a │ court to look at an apportionment has to be in front of one before December 31. │ │ 5. 435 IS NOT IN THE CONSTITUTION. │ The cap is a 1911 statute made permanent in 1929, and the average district has │ grown from about 210,000 people to about 761,000 since. Every zero-sum state-vs- │ state fight in this map exists because one number stopped moving in 1929. ``` ## Notes - **The live deadline is April 1, 2027, and it is statutory rather than constitutional.** Under 13 U.S.C. § 141(f) the Secretary must report the *subjects* proposed for a census to the congressional committees of jurisdiction three years out, and the *questions* two years out. For a census dated April 1, 2030, that is a subjects report due in **April 2027** — seven months out as of September 2026 — and a questions report due in April 2028. This matters more than any executive statement to date: an immigration-status question that never appears in the subjects report arrives at the printer with a statutory defect on top of whatever constitutional problem it has. It also cuts the other way, which is why the [[2030 Census]] question fight is best understood as a 2027–2029 fight: a question reported in 2027 can still be removed before forms are printed. - **The August 2025 "new census" announcement has produced no implementing document, and two statutes stand in the way of the most obvious reading of it.** If it meant an off-cycle recount, 13 U.S.C. § 141(e)(2) forbids using mid-decade census information for apportionment or for drawing congressional districts. If it meant excluding people from the base of the regular count, that is the question the Supreme Court twice declined to answer. As of this writing the operative legal position is the one the statutes set, not the one the announcement described — but note what actually changed on **January 20, 2025**: [[Executive Order 14148]] revoked [[Executive Order 13986]], the Biden order that had affirmatively directed the Secretary to report whole-persons tabulations. Nothing replaced it. The whole-persons rule still governs because 2 U.S.C. § 2a and the [[Fourteenth Amendment]] say so, not because an executive order says so. - **The most revealing line in the current litigation is the federal defendants' own motion.** In [[Missouri v. Department of Commerce]], filed January 30, 2026 in the Eastern District of Missouri, Missouri asks the court to declare the 2020 count unlawful, order it redone, and bar counting people without lawful status in 2030 — the outcome the administration has publicly demanded. On **June 26, 2026 the federal defendants moved to stay the case.** A government that wanted the relief would not need the suit paused; a stay is what a defendant asks for when a merits ruling is more dangerous than the status quo. The court had already **denied a three-judge panel on April 3, 2026**, which keeps the case on the ordinary appellate track rather than the direct-to-Supreme-Court route the plaintiffs sought. - **Two closed doors and one that has never been tested.** [[Department of Commerce v. New York]] (2019) blocked the 2020 citizenship *question* because the stated justification was contrived — a ruling about pretext, not about citizenship questions as such. [[Trump v. New York]] (2020) vacated the challenge to the July 2020 memorandum excluding people without lawful status from the apportionment *base*, on ripeness. [[Franklin v. Massachusetts]] (1992) held the presidential transmittal is not reviewable agency action. Put together: the merits question — may anyone lawfully present be excluded from "the whole number of persons"? — has never been answered, and the step at which it would be executed is the step least amenable to review. - **Sampling and imputation are not the same thing, and the difference has decided a seat.** 13 U.S.C. § 195 permits statistical sampling throughout Title 13 *except* for the apportionment determination, and the Court so held in 1999. But [[Utah v. Evans]] (2002) upheld hot-deck imputation — filling an unresolved household from a similar neighboring one — as enumeration rather than sampling, and the seat at stake went to North Carolina rather than Utah. The practical consequence is stated in the map: the apportionment total is the one federal statistic with no correction mechanism. The post-enumeration survey measures [[Census Undercount]] precisely and changes nothing. - **Officeholders:** none are named in the map itself. As of September 2026, the Commerce Secretary is [[Howard Lutnick]] (confirmed February 18, 2025), and the Census Bureau has had **no Senate-confirmed director since September 2025** — George Cook has served as acting director since September 19, 2025. A permanent-director vacancy across the entire 2030 design window is itself a structural fact about who is making the 2027 subjects-report decision. ## See also - [[Census Data Products Tree]] — the apportionment tabulation in its full context: one of exactly two census products carrying a statutory deadline, and what the rest of the cycle produces on no deadline at all. - [[How the Census Is Actually Counted]] — the upstream half: how a state total gets produced in the first place, from the address list through imputation - [[How a Redistricting Map Is Drawn and Challenged]] — the next stage: what states do with the seats this map assigns - [[Congressional Apportionment Mathematics]] — the formula in depth: the paradoxes, the methods Congress rejected, and the impossibility result - [[Census Bureau]] · [[Department of Commerce]] — the agency and the department that owns it - [[2020 Census]] · [[2030 Census]] — the two counts this map sits between - [[Method of Equal Proportions]] · [[Apportionment]] — the formula, and the unrelated budget term that shares its name - [[Permanent Apportionment Act of 1929]] · [[Congressional Apportionment Amendment]] — the statute that froze the House, and the amendment that would have governed its size instead - [[Census Citizenship Question]] · [[Census Undercount]] · [[Differential Privacy]] · [[American Community Survey]] — the contested inputs and the data around them - [[Department of Commerce v. New York]] · [[Trump v. New York]] · [[Franklin v. Massachusetts]] · [[Utah v. Evans]] · [[Evenwel v. Abbott]] · [[Wesberry v. Sanders]] — the case law - [[Missouri v. Department of Commerce]] — the live 2026 challenge - [[Executive Order 13986]] · [[Executive Order 14148]] — the revocation pair that removed the executive whole-persons policy - [[One Person One Vote]] · [[Gerrymandering]] · [[Mid-Decade Redistricting]] — the doctrines downstream - [[Electoral College]] · [[Electoral College Process Flow]] — the other thing state seat counts determine - [[Redistricting Timeline 2025-2026]] — the current-events layer - [[Foundations Hub]] — parent hub for the map series - [[2026 Midterms Hub]] — the election this map's numbers are already fixed for