Diversity jurisdiction sounds simple — different states, enough money at stake — but the details that actually control whether removal succeeds are easy to get wrong, and getting them wrong can mean remand, wasted time, and sometimes fee awards against the removing party. Complete diversity has to exist among every party, not just the named plaintiff and defendant, and the amount in controversy has to be evaluated the way courts actually evaluate it, not the way the complaint happens to phrase it.

This guide walks through the specific questions to answer before deciding whether diversity jurisdiction supports removing a case from state to federal court. It is an educational explainer of general concepts, not legal advice — removal procedure, deadlines, and the treatment of specific issues like citizenship of business entities vary by circuit and should be confirmed against current law before acting.

Diversity jurisdiction under the federal removal statute generally requires complete diversity: no plaintiff can share citizenship with any defendant, on either side of the case, not merely between the primary named parties. A single non-diverse defendant, even one added late or seemingly minor to the case, can defeat the entire basis for removal unless that party's presence can be independently addressed.

Determine each party's citizenship carefully rather than assuming it from an address on the complaint. An individual's citizenship is their state of domicile, which is not necessarily where they currently reside or were served. Watch particularly for parties whose citizenship is not obvious from the pleadings — trusts, estates, and government entities can each carry citizenship rules that differ from the general rule for individuals.

Corporate citizenship generally follows the state of incorporation and the state of the corporation's principal place of business, both of which count. Limited liability companies and other unincorporated entities are typically treated differently — for diversity purposes, they generally take on the citizenship of every one of their members, which can require tracing through multiple layers of ownership if a member is itself an LLC or partnership.

Diversity jurisdiction also requires the amount in controversy to exceed the statutory threshold. Where the complaint itself does not specify a dollar amount, or specifies an amount courts might view with skepticism, the removing party generally must show the jurisdictional amount is more likely than not satisfied, based on the allegations, the type of relief sought, and any other evidence bearing on the case's value.

Build this showing deliberately rather than assuming it. Look at comparable verdicts or settlements for similar claims, the specific categories of damages alleged, any request for punitive damages or injunctive relief with an attributable value, and attorney fee-shifting provisions where the underlying claim allows fee recovery, since some jurisdictions count that toward the amount in controversy and others do not.

Even a case that clearly satisfies diversity and the amount in controversy can be sent back to state court on a purely procedural basis, so confirm these separately from the substantive jurisdictional analysis. Removal is generally subject to a strict deadline running from receipt of the initial pleading or a later paper first revealing removability, and missing it forfeits the right to remove even where jurisdiction otherwise exists.

Also check the forum-defendant rule, which in many circumstances bars removal based on diversity if a defendant is a citizen of the state where the action was filed, even where complete diversity exists among all parties. And confirm every properly joined and served defendant has consented to removal where that is required, since a missing consent is a common, avoidable basis for remand.