Shall — in plain language

Plain language

must; is required to do this; has no choice but to do this

• must
• is required to
• has an obligation to
• is obligated to

What to watch for

• 'Shall' is mandatory, not aspirational — a plain rewrite must use 'must' or 'is required to,' not 'should' or 'is expected to,' which leave room for discretion.
• Courts have occasionally interpreted 'shall' as directory rather than strictly mandatory, especially in procedural rules; the translation should flag when this ambiguity could affect enforcement.
• 'Shall not' is a prohibition, not merely the absence of a duty; it should be translated as 'must not' or 'is not allowed to,' not as 'does not have to.'
• Modern plain-language drafting guides recommend replacing 'shall' with 'must' to avoid interpretive disputes; when translating older documents, preserve the mandatory force even if the word is archaic.

Distinguishing from Similar Terms. "Shall," "must," "may," and "should" each occupy a distinct level of obligation. "Shall" and "must" both impose mandatory duties; "may" grants a permission or option; "should" is merely advisory. When simplifying legal text, it is critical not to flatten "shall" into "should" or "may" — doing so transforms a requirement into a recommendation and can fundamentally change each party's rights and remedies.

Context-Dependent Meaning. The meaning of "shall" shifts when negated. Affirmative "shall" (the party shall do X) creates a positive duty to act. Negative "shall not" (no party shall do Y) creates a prohibition — an outright ban. A plain-language translation must reflect that difference: affirmative "shall" becomes "must," while "shall not" becomes "must not" or "is not allowed to."

Common Misunderstandings by Non-Lawyers.

• "'Shall' is just a formal way of saying 'will' or 'should.'" (No — in legal documents, "shall" is mandatory; it means the party is required to act, and a failure to comply can trigger a breach or legal penalty.)
• "'Shall not' means the party doesn't have to do something." (No — "shall not" is a prohibition; it means the party is forbidden from doing it, not merely excused from doing it.)
• "Courts always treat 'shall' as mandatory, so there is no ambiguity." (Not always — in a small number of procedural contexts, particularly older statutes, courts have read "shall" as directory, meaning a minor failure to comply may not void the result. This is the exception, not the rule.)

Legal definition

"Shall" is the principal word in U.S. legal drafting for imposing a mandatory obligation. When a contract or statute says a party "shall" do something, that party has a binding duty to perform the action — not a suggestion, not an option, not a goal. The word traces to Old English, where it carried the sense of owing something, and it entered formal legal instruments to signal that the obligation was absolute. Courts in the United States generally treat "shall" in a statute or contract as mandatory, meaning a failure to comply has legal consequences, though in a small number of procedural contexts courts have read it as merely directory. Modern drafting reformers increasingly prefer "must" over "shall" to remove this residual ambiguity, so newer federal rules and plain-language statutes often replace "shall" with "must" throughout.

Meanings by context

prohibitory drafting: must not do; is forbidden from doing

older statutory or formal drafting: will (future tense only — no duty intended)

Examples

Where you'll see it

• contract and lease clauses imposing duties on parties
• statutes and regulations imposing duties on agencies or individuals
• court orders and judgments
• corporate bylaws and operating agreements
• regulatory compliance requirements

Related terms

• must
• may
• mandatory
• can
• obligation
• will

Word details

Pronunciation

SHAL

Part of speech

verb

Origin

Old English — from Old English 'sceal' — to owe, to be under an obligation

Domains

contract law, statutory interpretation, administrative law, civil procedure

Frequency

very common

Formality

high