Missouri Condo Quorum & Supermajority Calculator — 20% Quorum, 67% Amendment, 80% Termination (Mo. Rev. Stat. Ch. 448)

How this calculator works

This is a quorum-and-threshold validator for Missouri condominium unit-owner votes under the Missouri Uniform Condominium Act. Given the total units, in-person attendance, proxy count, mail or electronic ballot count, vote type, and any declaration-specified overrides, it returns:

1. Whether quorum has been met (total ballots compared against the effective quorum requirement under Mo. Rev. Stat. Sec. 448.3-109 or the declaration-specified override).
2. The yes votes required to pass for the vote type — 67% of total for declaration amendments under Sec. 448.2-117, 80% of total for termination under Sec. 448.2-118, majority of those present for board removal under Sec. 448.3-103, majority of quorum at the rejection meeting for budget rejection under Sec. 448.3-115, and majority of quorum for regular votes.
3. The current outcome (PASSED, FAILED, PENDING, or NO-QUORUM) based on the supplied vote tally.

The budget-rejection vote type uses an inverse-vote convention: yes votes are treated as REJECT votes, and the outcome label changes accordingly. If the rejection threshold is met, the budget is REJECTED; if not, the budget is RATIFIED automatically under Sec. 448.3-115.

Use the calculator before convening a unit-owner meeting to confirm the procedural framework, during ballot counting to validate the threshold, and after a meeting to memorialize the outcome in the secretary's minutes.

The relevant Mo. Rev. Stat. Ch. 448 statute

The Missouri Uniform Condominium Act lives at Mo. Rev. Stat. Ch. 448 and applies in full to condominiums created on or after September 28, 1983. Older condominiums (pre-1983) remain under the Missouri Condominium Property Act with a parallel framework, though the modern Ch. 448 operating provisions (including the voting framework) have been broadly applied across Missouri practice. This calculator covers the modern Ch. 448 voting framework.

Mo. Rev. Stat. Sec. 448.3-109 — Default quorum at unit-owner meetings is 20% of the votes in the association unless the declaration or bylaws specify otherwise. The 20% default matches the Uniform Condominium Act model and is consistent with peer UCA-derived states.

Mo. Rev. Stat. Sec. 448.2-117 — Declaration amendment requires at least 67% of the votes in the association. This is a TOTAL-VOTES threshold (not 67% of those voting). The declaration may specify higher; it cannot specify lower than 67% for general declaration amendments.

Mo. Rev. Stat. Sec. 448.2-117 (heightened amendments) — Certain declaration amendments require a higher threshold or UNANIMOUS consent: changes to allocated interests, unit boundaries, conversion of a unit into common elements, increase in the number of units, and similar property-affecting changes. These are the highest-threshold actions under the Missouri UCA.

Mo. Rev. Stat. Sec. 448.2-118 — Termination of the condominium requires 80% of the votes in the association. The declaration may specify higher (some require 90% or unanimous consent). Termination dissolves the condominium.

Mo. Rev. Stat. Sec. 448.3-103 — Executive board member removal by a majority of unit owners present and entitled to vote at a meeting where a quorum is present. The "majority of those present and voting" standard is materially easier than the OF-TOTAL thresholds.

Mo. Rev. Stat. Sec. 448.3-106 — Bylaws amendment per bylaws specification; absent specification, the default majority of quorum applies.

Mo. Rev. Stat. Sec. 448.3-115 — Budget ratification by REJECTION mechanism. Board adopts the budget; unit owners may REJECT by majority of unit owners present at the rejection meeting; no rejection equals automatic ratification.

Missouri-specific gotchas (nonjudicial deed-of-trust foreclosure, 21-day limited redemption window)

MAJORITY OF TOTAL vs MAJORITY OF QUORUM. The two thresholds produce different outcomes when turnout is low. The Missouri UCA uses OF-TOTAL for declaration amendments (Sec. 448.2-117 at 67%) and termination (Sec. 448.2-118 at 80%). The UCA uses OF-QUORUM (or "of those present and voting") for board removal (Sec. 448.3-103), budget rejection (Sec. 448.3-115), and regular governance. The OF-TOTAL thresholds are intentionally hard to reach for property-affecting changes; the OF-QUORUM thresholds make governance practical at typical Missouri turnout levels (often 30 to 40%).

A DECLARATION AMENDMENT CAN FAIL EVEN WITH 100% OF VOTERS APPROVING. In an 80-unit association with 50% turnout (40 voters), 40 yes votes (100% of voters) is only 50% of total — well short of the 54-vote (67%) threshold and the amendment FAILS. Boards routinely announce declaration amendments as passed based on majority-of-voters math; this is wrong. The calculator distinguishes the two thresholds explicitly to prevent this error.

THE 20% QUORUM DEFAULT MATCHES OTHER UCA STATES. Missouri's 20% default quorum is consistent with Minnesota MCIOA (Sec. 515B.3-109) and Connecticut UCIOA (CGS Sec. 47-250(c)) — all are 20%. Washington WUCIOA is 25%; California Davis-Stirling is 50%. The 20% Missouri / Minnesota / Connecticut floor reflects the UCA model's accommodation of low-turnout community-association practice. Practical effect: regular Missouri condo votes can be conducted with modest turnout, but ambitious thresholds (declaration amendment at 67% of total) still require aggressive outreach.

MISSOURI DOES NOT LICENSE COMMUNITY ASSOCIATION MANAGERS. Florida (LCAM), Illinois (CAM), Nevada (CAM), and Virginia (CIC manager) all require state licensure of CAMs. Missouri does not. The Mo. Rev. Stat. Ch. 448 compliance work falls to the association attorney and the managing agent under contract. Boards in Missouri condo projects should expect to engage the association attorney earlier in the meeting-planning cycle than in states with licensed CAMs because there is no state-licensed manager handling procedural compliance independently.

BUDGET REJECTION FAVORS THE BOARD. Under Sec. 448.3-115, the board's proposed budget is RATIFIED unless a majority of unit owners PRESENT at the rejection meeting affirmatively reject. The Missouri threshold of "majority of attendees at the rejection meeting" is more achievable than Connecticut's "majority of all unit owners" under CGS Sec. 47-261b but still favors the board's proposal. Boards should anticipate that their budgets typically pass unless owners actively organize opposition.

BOARD REMOVAL IS EASIER THAN DECLARATION AMENDMENT. A board member can be removed by a majority of those present at a properly noticed meeting with quorum (typically 9 votes in an 80-unit, 20%-turnout meeting). A declaration amendment requires 54 of 80 votes. The threshold contrast is intentional — the Missouri UCA treats governance (board composition) as more accountable to active engagement and property rights (declaration content) as requiring broad consent.

HEIGHTENED DECLARATION AMENDMENTS REQUIRE HIGHER OR UNANIMOUS CONSENT. Sec. 448.2-117 lists categories of declaration amendments that require a higher threshold or UNANIMOUS consent — changes to allocated interests (a unit's vote allocation or common-expense allocation), unit boundaries, conversion to common elements, increase in the number of units, and similar property-affecting changes. The calculator does NOT model these heightened-threshold categories separately; if your vote type falls into a heightened category, the 67% threshold understates the requirement.

PROXIES ARE COMMON BUT MUST BE CURRENT. Mo. Rev. Stat. Sec. 448.3-110 permits proxies for unit-owner voting unless prohibited. Missouri bylaws commonly specify an 11-month maximum proxy validity. Proxies older than the period are invalid even if all other elements are met. For OF-TOTAL threshold votes, aggressive proxy campaigns are typically necessary to reach the threshold.

What this calculator does NOT model

The calculator implements the Missouri UCA QUORUM-AND-SUPERMAJORITY math. It does NOT:

• Model the heightened-threshold and unanimous-consent categories under Sec. 448.2-117 (unit-boundary changes, allocated-interest changes, conversion to common elements). If your vote type falls into one of these categories, the 67% threshold understates the requirement; consult counsel.
• Model the bylaws-amendment procedures under Sec. 448.3-106 in detail — the bylaws specify the threshold and the calculator uses a default majority-of-quorum if no declaration override is supplied.
• Validate the form of proxies (signature, witness, expiration, delegation chain) under Sec. 448.3-110.
• Model the executive-board meeting procedures (board meetings have separate quorum and notice requirements).
• Model the special-assessment ratification mechanics under Sec. 448.3-115 — special assessments above a declaration-specified threshold typically go through the rejection mechanism.
• Validate compliance with the Sec. 448.3-109 notice requirements that gate the meeting.
• Cover voting under the older Missouri Condominium Property Act provisions that may govern pre-1983 projects in part.

For any consequential vote, retain Missouri counsel with Mo. Rev. Stat. Ch. 448 experience to oversee the procedural compliance review.

Sources

Last reviewed: 2026-05-17 against:

• Mo. Rev. Stat. Ch. 448 (Missouri Uniform Condominium Act).
• Mo. Rev. Stat. Sec. 448.3-109 — 20% default quorum.
• Mo. Rev. Stat. Sec. 448.2-117 — declaration amendment 67% of total default; heightened-threshold categories.
• Mo. Rev. Stat. Sec. 448.2-118 — termination 80% of total default.
• Mo. Rev. Stat. Sec. 448.3-103 — executive board removal.
• Mo. Rev. Stat. Sec. 448.3-106 — bylaws amendment.
• Mo. Rev. Stat. Sec. 448.3-110 — proxy authorization.
• Mo. Rev. Stat. Sec. 448.3-115 — budget adoption and rejection mechanism.
• Missouri Condominium Property Act — parallel framework for pre-1983 condominiums.
• Community Associations Institute Heartland Chapter practitioner materials covering Missouri condo governance.