diff --git a/Cargo.toml b/Cargo.toml
index 711ffc2..098a9ac 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -15,7 +15,7 @@ axum = ["dep:axum", "dep:tower", "dep:hyper", "dep:http-body-util"]
 diesel = ["dep:diesel"]
 
 [dependencies]
-chrono = { version = "0.4.34", features = ["clock"], default-features = false }
+chrono = { version = "0.4.34", features = ["clock", "serde"], default-features = false }
 serde = { version = "1.0.197", features = ["derive"] }
 async-trait = "0.1.77"
 url = { version = "2.5.0", features = ["serde"] }
diff --git a/examples/local_federation/objects/person.rs b/examples/local_federation/objects/person.rs
index 0ae402f..076e698 100644
--- a/examples/local_federation/objects/person.rs
+++ b/examples/local_federation/objects/person.rs
@@ -119,7 +119,7 @@ impl DbUser {
         if use_queue {
             queue_activity(&activity, self, recipients, data).await?;
         } else {
-            let sends = SendActivityTask::prepare(&activity, self, recipients, data).await?;
+            let sends = SendActivityTask::prepare(&activity, self, recipients, None, data).await?;
             for send in sends {
                 send.sign_and_send(data).await?;
             }
diff --git a/src/activity_queue.rs b/src/activity_queue.rs
index abb5800..98edbf6 100644
--- a/src/activity_queue.rs
+++ b/src/activity_queue.rs
@@ -49,7 +49,7 @@ where
     ActorType: Actor,
 {
     let config = &data.config;
-    let tasks = build_tasks(activity, actor, inboxes, data).await?;
+    let tasks = build_tasks(activity, actor, inboxes, None, data).await?;
 
     for task in tasks {
         // Don't use the activity queue if this is in debug mode, send and wait directly
diff --git a/src/activity_sending.rs b/src/activity_sending.rs
index f16ef37..94158a2 100644
--- a/src/activity_sending.rs
+++ b/src/activity_sending.rs
@@ -19,10 +19,10 @@ use reqwest::header::{HeaderMap, HeaderName, HeaderValue};
 use reqwest_middleware::ClientWithMiddleware;
 use serde::Serialize;
 use std::{
-    self,
     fmt::{Debug, Display},
     time::{Duration, SystemTime},
 };
+use chrono::{DateTime, Utc};
 use tracing::debug;
 use url::Url;
 
@@ -51,10 +51,13 @@ impl SendActivityTask {
     /// - `inboxes`: List of remote actor inboxes that should receive the activity. Ignores local actor
     ///              inboxes. Should be built by calling [crate::traits::Actor::shared_inbox_or_inbox]
     ///              for each target actor.
+    /// - `published`: Time when the activity was created, so that recipient can apply activities
+    ///                in correct order.
     pub async fn prepare<Activity, Datatype, ActorType>(
         activity: &Activity,
         actor: &ActorType,
         inboxes: Vec<Url>,
+        published: Option<DateTime<Utc>>,
         data: &Data<Datatype>,
     ) -> Result<Vec<SendActivityTask>, Error>
     where
@@ -62,7 +65,7 @@ impl SendActivityTask {
         Datatype: Clone,
         ActorType: Actor,
     {
-        build_tasks(activity, actor, inboxes, data).await
+        build_tasks(activity, actor, inboxes, published, data).await
     }
 
     /// convert a sendactivitydata to a request, signing and sending it
@@ -117,6 +120,7 @@ pub(crate) async fn build_tasks<'a, Activity, Datatype, ActorType>(
     activity: &'a Activity,
     actor: &ActorType,
     inboxes: Vec<Url>,
+    published: Option<DateTime<Utc>>,
     data: &Data<Datatype>,
 ) -> Result<Vec<SendActivityTask>, Error>
 where
@@ -127,7 +131,10 @@ where
     let config = &data.config;
     let actor_id = activity.actor();
     let activity_id = activity.id();
-    let activity_serialized: Bytes = serde_json::to_vec(activity)
+    let activity_serialized: Bytes = match published {
+        Some(published) => serde_json::to_vec(&WithPublished::new(activity, published)),
+        None => serde_json::to_vec(activity)
+    }
         .map_err(|e| Error::SerializeOutgoingActivity(e, format!("{:?}", activity)))?
         .into();
     let private_key = get_pkey_cached(data, actor).await?;
@@ -210,6 +217,24 @@ pub(crate) fn generate_request_headers(inbox_url: &Url) -> HeaderMap {
     headers
 }
 
+/// Wrapper struct that adds `published` field with timestamp to outgoing activities. Important that
+/// the timestamp includes milliseconds and timezone.
+#[derive(Serialize)]
+struct WithPublished<T> {
+    published: DateTime<Utc>,
+    #[serde(flatten)]
+    inner: T,
+}
+
+impl<T> WithPublished<T> {
+    pub fn new(inner: T, published: DateTime<Utc>) -> WithPublished<T> {
+        Self {
+            published,
+            inner,
+        }
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
diff --git a/src/traits.rs b/src/traits.rs
index 9fdec27..ee680f0 100644
--- a/src/traits.rs
+++ b/src/traits.rs
@@ -343,7 +343,7 @@ pub mod tests {
         error::Error,
         fetch::object_id::ObjectId,
         http_signatures::{generate_actor_keypair, Keypair},
-        protocol::{public_key::PublicKey, verification::verify_domains_match},
+        protocol::{verification::verify_domains_match},
     };
     use activitystreams_kinds::{activity::FollowType, actor::PersonType};
     use once_cell::sync::Lazy;