diff --git a/irc/client.go b/irc/client.go
index 14efecd8..2e814ce9 100644
--- a/irc/client.go
+++ b/irc/client.go
@@ -41,8 +41,7 @@ const (
 	DefaultMaxLineLen = 512
 
 	// IdentTimeout is how long before our ident (username) check times out.
-	IdentTimeout         = time.Second + 500*time.Millisecond
-	IRCv3TimestampFormat = utils.IRCv3TimestampFormat
+	IdentTimeout = time.Second + 500*time.Millisecond
 	// limit the number of device IDs a client can use, as a DoS mitigation
 	maxDeviceIDsPerClient = 64
 	// maximum total read markers that can be stored
@@ -1463,7 +1462,7 @@ func (session *Session) sendFromClientInternal(blocking bool, serverTime time.Ti
 
 func composeMultilineBatch(batchID, fromNickMask, fromAccount string, isBot bool, tags map[string]string, command, target string, message utils.SplitMessage) (result []ircmsg.Message) {
 	batchStart := ircmsg.MakeMessage(tags, fromNickMask, "BATCH", "+"+batchID, caps.MultilineBatchType, target)
-	batchStart.SetTag("time", message.Time.Format(IRCv3TimestampFormat))
+	batchStart.SetTag("time", message.Time.Format(utils.IRCv3TimestampFormat))
 	batchStart.SetTag("msgid", message.Msgid)
 	if fromAccount != "*" {
 		batchStart.SetTag("account", fromAccount)
@@ -1571,7 +1570,7 @@ func (session *Session) setTimeTag(msg *ircmsg.Message, serverTime time.Time) {
 		if serverTime.IsZero() {
 			serverTime = time.Now()
 		}
-		msg.SetTag("time", serverTime.UTC().Format(IRCv3TimestampFormat))
+		msg.SetTag("time", serverTime.UTC().Format(utils.IRCv3TimestampFormat))
 	}
 }
 
diff --git a/irc/getters.go b/irc/getters.go
index 902614f7..29f97c75 100644
--- a/irc/getters.go
+++ b/irc/getters.go
@@ -517,7 +517,7 @@ func (client *Client) GetReadMarker(cfname string) (result string) {
 	t, ok := client.readMarkers[cfname]
 	client.stateMutex.RUnlock()
 	if ok {
-		return fmt.Sprintf("timestamp=%s", t.Format(IRCv3TimestampFormat))
+		return fmt.Sprintf("timestamp=%s", t.Format(utils.IRCv3TimestampFormat))
 	}
 	return "*"
 }
diff --git a/irc/handlers.go b/irc/handlers.go
index d0d619c0..538c2126 100644
--- a/irc/handlers.go
+++ b/irc/handlers.go
@@ -719,7 +719,7 @@ func chathistoryHandler(server *Server, client *Client, msg ircmsg.Message, rb *
 				for _, target := range targets {
 					name := server.UnfoldName(target.CfName)
 					rb.Add(nil, server.name, "CHATHISTORY", "TARGETS", name,
-						target.Time.Format(IRCv3TimestampFormat))
+						target.Time.Format(utils.IRCv3TimestampFormat))
 				}
 			} else if channel != nil {
 				channel.replayHistoryItems(rb, items, true)
@@ -754,7 +754,7 @@ func chathistoryHandler(server *Server, client *Client, msg ircmsg.Message, rb *
 			msgid, err = history.NormalizeMsgid(value), nil
 			return
 		} else if identifier == "timestamp" {
-			timestamp, err = time.Parse(IRCv3TimestampFormat, value)
+			timestamp, err = time.Parse(utils.IRCv3TimestampFormat, value)
 			if err == nil {
 				timestamp = timestamp.UTC()
 				if timestamp.Before(unixEpoch) {
@@ -3055,14 +3055,14 @@ func markReadHandler(server *Server, client *Client, msg ircmsg.Message, rb *Res
 
 	// "MARKREAD client set command": MARKREAD <target> <timestamp>
 	readTimestamp := strings.TrimPrefix(msg.Params[1], "timestamp=")
-	readTime, err := time.Parse(IRCv3TimestampFormat, readTimestamp)
+	readTime, err := time.Parse(utils.IRCv3TimestampFormat, readTimestamp)
 	if err != nil {
 		rb.Add(nil, server.name, "FAIL", "MARKREAD", "INVALID_PARAMS", utils.SafeErrorParam(readTimestamp), client.t("Invalid timestamp"))
 		return
 	}
 	readTime = readTime.UTC()
 	result := client.SetReadMarker(cftarget, readTime)
-	readTimestamp = fmt.Sprintf("timestamp=%s", result.Format(IRCv3TimestampFormat))
+	readTimestamp = fmt.Sprintf("timestamp=%s", result.Format(utils.IRCv3TimestampFormat))
 	// inform the originating session whether it was a success or a no-op:
 	rb.Add(nil, server.name, "MARKREAD", unfoldedTarget, readTimestamp)
 	if result.Equal(readTime) {
diff --git a/irc/histserv.go b/irc/histserv.go
index 8e28dafc..35b2e9b4 100644
--- a/irc/histserv.go
+++ b/irc/histserv.go
@@ -164,7 +164,7 @@ func histservExportHandler(service *ircService, server *Server, client *Client,
 
 	config := server.Config()
 	// don't include the account name in the filename because of escaping concerns
-	filename := fmt.Sprintf("%s-%s.json", utils.GenerateSecretToken(), time.Now().UTC().Format(IRCv3TimestampFormat))
+	filename := fmt.Sprintf("%s-%s.json", utils.GenerateSecretToken(), time.Now().UTC().Format(utils.IRCv3TimestampFormat))
 	pathname := config.getOutputPath(filename)
 	outfile, err := os.Create(pathname)
 	if err != nil {
diff --git a/irc/message_cache.go b/irc/message_cache.go
index 2d731823..f56568b3 100644
--- a/irc/message_cache.go
+++ b/irc/message_cache.go
@@ -45,7 +45,7 @@ type MessageCache struct {
 
 func addAllTags(msg *ircmsg.Message, tags map[string]string, serverTime time.Time, msgid, accountName string, isBot bool) {
 	msg.UpdateTags(tags)
-	msg.SetTag("time", serverTime.Format(IRCv3TimestampFormat))
+	msg.SetTag("time", serverTime.Format(utils.IRCv3TimestampFormat))
 	if accountName != "*" {
 		msg.SetTag("account", accountName)
 	}