The application shall be supported by an affidavit showing that the plaintiff on the facts presented would be entitled to a judgment on the claim upon which the attachment is based.
§ 484.030.Affidavit Supporting Application
Title 6.5. Attachment · Chapter 4. Noticed Hearing Procedure for Obtaining Writ of Attachment · Article 1. Right to Attach Order; Issuance of Writ of Attachment · Enacted 1974 · no amendments on record · Last verified July 28, 2026
In one sentenceSection 484.030 requires the attachment application to be backed by an affidavit showing that, on the facts presented, the plaintiff would be entitled to a judgment on the claim the attachment is based on.
Full Text of § 484.030
Plain-English Summary
This is the affidavit that carries the weight at the attachment hearing. It has to show, on the facts the plaintiff presents, that the plaintiff would win a judgment on the underlying claim. That's the factual foundation the court tests against the probable-validity standard defined in § 481.190 — a claim has probable validity when it's more likely than not the plaintiff will get a judgment on it.
Nothing about this affidavit decides the case. Section 484.050(b) makes clear the attachment hearing determines probable validity only, not actual validity, and § 484.100 keeps the court's attachment-hearing findings out of evidence at trial. The § 484.030 affidavit exists to support a preliminary, provisional remedy — not to substitute for proving the case on the merits.
Chapter 5's ex parte procedure requires the same probable-validity showing, layered with additional affidavit requirements. Section 485.210(c)(1) repeats this exact language for the emergency track, then adds the great-or-irreparable-injury and non-exemption showings that only the ex parte procedure demands.
Frequently Asked Questions
What must the affidavit supporting an attachment application show?
That the plaintiff, on the facts presented, would be entitled to a judgment on the claim the attachment is based on.
Does this affidavit have to prove the case the way trial evidence would?
No. Section 484.050(b) explains that the hearing decides probable validity, not actual validity — the merits get resolved later in the action itself.
How does this affidavit connect to the "probable validity" standard?
Section 481.190 defines probable validity as more likely than not; the § 484.030 affidavit is the evidence the court uses to decide whether the plaintiff clears that bar.
Amendment History
Added by Stats. 1974, Ch. 1516.
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: probable validity affidavit california attachmentaffidavit supporting writ of attachment