(a) Whenever a writ is issued, a defendant who has appeared in the action may apply by noticed motion to the court in which the action is pending for an order permitting the defendant to substitute an undertaking for any of his property in the state which has been or is subject to being attached.
§ 489.310.Generally
Title 6.5. Attachment · Chapter 9. Undertakings · Article 3. Undertaking to Obtain Release of Attachment or Protective Order · Last amended 1976 · Last verified July 28, 2026
In one sentenceSection 489.310 lets a defendant who has appeared in the action substitute an undertaking for attached or attachable property, requiring a sworn description of the property when only part of it is being released or protected, and setting the undertaking amount at the lesser of the property's value or the amount the writ secures.
Full Text of § 489.310
(b) In a case (1) where the defendant applies for an order to release a portion of property which has been attached or (2) where the defendant applies for an order preventing the attachment of property and the amount of the undertaking to be given is less than the amount to be secured by the attachment, the application shall include a statement, executed under oath, describing the property to be so released or so protected from attachment.
(c) The defendant shall file an undertaking to pay the plaintiff the value of the property released not exceeding the amount of any judgment which may be recovered by the plaintiff in the action against the defendant. The amount of the undertaking filed pursuant to this section shall be equal to the lesser of (1) the value of the property attached or prevented from being attached or (2) the amount specified by the writ to be secured by the attachment. The court shall issue such order upon the condition that a sufficient undertaking be filed.
(d) Where an action is against more than one defendant, any defendant may make such application. The filing of an undertaking by such defendant shall not subject him to any demand against any other defendant; however, the levying officer shall not be prevented thereby from attaching, or be obliged to release from attachment, any property of any other defendant. Where all the defendants do not join in the application, the application shall include a statement, executed under oath, describing the character of the defendant's title to the property and the manner in which the defendant acquired such title and stating whether any other defendant who has not joined in the application has an interest in the property. Where two or more defendants have an interest in the same property, a joint application and undertaking shall be filed to secure the release of such property.
Plain-English Summary
Attachment ties up specific property, and § 489.310 gives a defendant who has appeared a way to trade that property for a bond instead. On noticed motion, the defendant asks the court in which the action is pending to substitute an undertaking for property that has been, or could be, attached.
Subdivision (b) requires more detail when the defendant is asking for only partial relief -- releasing part of the attached property or protecting property from attachment while the undertaking secures less than the writ's full amount. In that situation the application must include a sworn statement describing the property being released or protected.
Subdivision (c) fixes the amount: the lesser of the property's value or the amount the writ secures. Subdivision (d) addresses multi-defendant cases -- any defendant may make the motion, and filing an undertaking does not expose that defendant to any other defendant's liabilities, though it also does not stop the levying officer from attaching, or require release of, other defendants' property. Where defendants share an interest in the same property, they must file a joint application and undertaking to release it.
Frequently Asked Questions
Can a defendant get attached property back by posting a bond instead?
Yes. Section 489.310(a) lets a defendant who has appeared in the action move by noticed motion for an order substituting an undertaking for property that has been or could be attached.
How is the undertaking amount calculated under § 489.310?
Subdivision (c) sets it at the lesser of the value of the property being released or protected, or the amount the writ of attachment secures.
If one of several defendants posts this undertaking, does it protect the other defendants' property too?
No. Section 489.310(d) states that one defendant's undertaking does not subject that defendant to demands from other defendants, and does not prevent the levying officer from attaching other defendants' property or require its release.
Amendment History
Amended by Stats. 1976, Ch. 437.
Source & verification. Section text is reproduced verbatim from
the Deering's California Codes Annotated / vLex. Enacted by the California Legislature.
Last verified July 28, 2026.
· Official source
Also known as: substitute undertaking for attached property californiarelease attachment by posting bondcalifornia attachment bond substitution