Passive Voice — ser + past participle

By the end of this lesson, you will be able to form and use the true passive voice (ser + past participle) in Spanish, make the past participle agree with the subject, and express the agent with por.

Introduction

English speakers use the passive voice constantly: "The novel was written by García Márquez." "The treaty was signed in 1848." Spanish has an equivalent structure, but it is used more selectively than in English — especially in written, formal, and journalistic contexts. Understanding the passive voice with ser is essential for reading newspapers, legal texts, and literary criticism at B2 level, and for producing formal writing that sounds genuinely educated.

Core Concept

Formation

Subject + ser (conjugated) + past participle (agreeing in gender and number) + por + agent (optional)

The past participle behaves like an adjective: it agrees with the grammatical subject.

Subject	ser	Past participle	Agent
La ley	fue	aprobada	por el parlamento.
Los documentos	fueron	firmados	por el presidente.
El puente	será	construido	por la empresa.
Las cartas	han sido	enviadas	(agent omitted)

Passive in All Tenses

Tense	Example
Present	El museo es visitado por miles de turistas cada año.
Preterite	El edificio fue demolido en 1990.
Imperfect	Antes, las cartas eran escritas a mano.
Future	La sentencia será anunciada mañana.
Present perfect	El acuerdo ha sido alcanzado tras meses de negociación.