In a federal lawsuit, a corporation may be served by “delivering a copy of the summons and of the complaint to an officer or general agent, or any other agent authorized by appointment or by law to receive service of process and—if the agent is one authorized by statute and the statute so requires—by also mailing a copy of each to the defendant.” Fed. R. Civ. P. 4(h)(1)(B).

Fed. R. Civ. P. 4(h)(1)(A) also provides that a corporation may be served according to Fed. R. Civ. P. 4(e)(1), which allows for service by methods approved by state law “where the district court is located or where service is made.”

For corporations in Colorado, service may be made “by delivering a copy of [the summons] to the registered agent for service,” or to an officer of the corporation, an officer's secretary or assistant, or the functional equivalent. Colo. R. Civ. P. 4(e)(4)(A), (F).

Substitute Service by Mail

If the registered agent of the entity “cannot with reasonable diligence be served,” then Colorado law allows “the entity [to] be served by registered mail or by certified mail, return receipt requested, addressed to the entity at its principal address.” Colo. Rev. Stat. § 70–90–704(2). Under this Colorado state statute, such substitute service is perfected “at the earliest of: (a) The date the entity receives the process, notice, or demand; (b) The date shown on the return receipt, if signed on behalf of the entity; or (c) Five days after mailing.”

Thus, after there have been multiple unsuccessful attempts at regular service, substitute service by mail on a Colorado corporation could be appropriate. Brand Q, Inc. v. All About Uniforms, Inc., No. 1:22-cv-01423-WJM-MDB, 2022 WL 14155979 (D. Colo. Oct. 24, 2022) (ordering substitute service by mail); A.O. Smith Corp. v. USA Smith Indus. Dev. Inc., No. 16-cv-2587-WJM-MJW, 2017 WL 2224539, at *2 (D. Colo. May 22, 2017) (service by registered mail was deemed effective because prior attempts at personal service on the entity's registered agent were unsuccessful); Kilthau v. Low T Med. Clinic, Inc., No. 14-cv-03309-MJW, 2015 WL 586262, at *1 (D. Colo. Feb. 11, 2015) (noting that the court had previously permitted substitute service on an entity by mail after personal service on the entity's registered agent could not be completed).

The attorneys at Thomas P. Howard, LLC litigate federal and state cases in Colorado.