diff --git a/src/channel.cpp b/src/channel.cpp
index 51b599b44..da7643d62 100644
--- a/src/channel.cpp
+++ b/src/channel.cpp
@@ -38,6 +38,13 @@ void Channel::addMessage(std::shared_ptr<Message> message)
 {
     std::shared_ptr<Message> deleted;
 
+    const QString &username = message->username;
+
+    if (!username.isEmpty()) {
+        // TODO: Add recent chatters display name. This should maybe be a setting
+        this->addRecentChatter(username);
+    }
+
     //    if (_loggingChannel.get() != nullptr) {
     //        _loggingChannel->append(message);
     //    }
@@ -49,6 +56,24 @@ void Channel::addMessage(std::shared_ptr<Message> message)
     this->messageAppended(message);
 }
 
+void Channel::addRecentChatter(const QString &username)
+{
+    std::lock_guard<std::mutex> lock(this->recentChattersMutex);
+
+    this->recentChatters.insert(username);
+}
+
+std::set<QString> Channel::getUsernamesForCompletions()
+{
+    std::set<QString> usernames;
+
+    this->recentChattersMutex.lock();
+    usernames.insert(this->recentChatters.begin(), this->recentChatters.end());
+    this->recentChattersMutex.unlock();
+
+    return usernames;
+}
+
 bool Channel::canSendMessage() const
 {
     return false;
diff --git a/src/channel.hpp b/src/channel.hpp
index ceca68f28..685503dbf 100644
--- a/src/channel.hpp
+++ b/src/channel.hpp
@@ -13,6 +13,7 @@
 #include <boost/signals2.hpp>
 
 #include <memory>
+#include <set>
 
 namespace chatterino {
 namespace messages {
@@ -30,16 +31,21 @@ public:
     virtual bool isEmpty() const;
     messages::LimitedQueueSnapshot<messages::SharedMessage> getMessageSnapshot();
 
-    // methods
     void addMessage(messages::SharedMessage message);
+    void addRecentChatter(const QString &username);
+
+    std::set<QString> getUsernamesForCompletions();
+
     QString name;
     QStringList modList;
 
+    std::mutex recentChattersMutex;
+    std::set<QString> recentChatters;
+
     virtual bool canSendMessage() const;
     virtual void sendMessage(const QString &message);
 
 private:
-    // variables
     messages::LimitedQueue<messages::SharedMessage> messages;
 
     // std::shared_ptr<logging::Channel> loggingChannel;
diff --git a/src/channelmanager.cpp b/src/channelmanager.cpp
index 6371de46e..3df5e97e4 100644
--- a/src/channelmanager.cpp
+++ b/src/channelmanager.cpp
@@ -5,6 +5,8 @@ using namespace chatterino::twitch;
 
 namespace chatterino {
 
+ChannelManager *ChannelManager::instance = nullptr;
+
 ChannelManager::ChannelManager(WindowManager &_windowManager, IrcManager &_ircManager)
     : windowManager(_windowManager)
     , ircManager(_ircManager)
@@ -12,6 +14,7 @@ ChannelManager::ChannelManager(WindowManager &_windowManager, IrcManager &_ircMa
     , mentionsChannel(new TwitchChannel(_ircManager, "/mentions", true))
     , emptyChannel(new TwitchChannel(_ircManager, "", true))
 {
+    ChannelManager::instance = this;
 }
 
 const std::vector<std::shared_ptr<Channel>> ChannelManager::getItems()
diff --git a/src/channelmanager.hpp b/src/channelmanager.hpp
index 0484360c4..02200e646 100644
--- a/src/channelmanager.hpp
+++ b/src/channelmanager.hpp
@@ -16,6 +16,8 @@ class ChannelManager
 public:
     explicit ChannelManager(WindowManager &_windowManager, IrcManager &_ircManager);
 
+    static ChannelManager *instance;
+
     WindowManager &windowManager;
     IrcManager &ircManager;
 
diff --git a/src/completionmanager.cpp b/src/completionmanager.cpp
index 51dfa41a3..520cf1d6e 100644
--- a/src/completionmanager.cpp
+++ b/src/completionmanager.cpp
@@ -1,11 +1,12 @@
 #include "completionmanager.hpp"
+#include "channelmanager.hpp"
 #include "common.hpp"
 #include "debug/log.hpp"
 #include "emotemanager.hpp"
 
 namespace chatterino {
 
-CompletionModel::CompletionModel(const std::string &_channelName)
+CompletionModel::CompletionModel(const QString &_channelName)
     : channelName(_channelName)
 {
 }
@@ -39,14 +40,14 @@ void CompletionModel::refresh()
 
     // Channel-specific: BTTV Channel Emotes
     std::vector<std::string> &bttvChannelEmoteCodes =
-        emoteManager.bttvChannelEmoteCodes[this->channelName];
+        emoteManager.bttvChannelEmoteCodes[this->channelName.toStdString()];
     for (const auto &m : bttvChannelEmoteCodes) {
         this->addString(m);
     }
 
     // Channel-specific: FFZ Channel Emotes
     std::vector<std::string> &ffzChannelEmoteCodes =
-        emoteManager.ffzChannelEmoteCodes[this->channelName];
+        emoteManager.ffzChannelEmoteCodes[this->channelName.toStdString()];
     for (const auto &m : ffzChannelEmoteCodes) {
         this->addString(m);
     }
@@ -57,7 +58,17 @@ void CompletionModel::refresh()
         this->addString(":" + m + ":");
     }
 
-    // TODO: Add Channel-specific: Usernames
+    // Channel-specific: Usernames
+    auto *channelManager = ChannelManager::instance;
+    auto c = channelManager->getTwitchChannel(this->channelName);
+    if (!c) {
+        return;
+    }
+    auto usernames = c->getUsernamesForCompletions();
+    for (const auto &username : usernames) {
+        this->addString(username);
+        this->addString('@' + username);
+    }
 }
 
 void CompletionModel::addString(const std::string &str)
@@ -66,6 +77,12 @@ void CompletionModel::addString(const std::string &str)
     this->emotes.push_back(qS(str) + " ");
 }
 
+void CompletionModel::addString(const QString &str)
+{
+    // Always add a space at the end of completions
+    this->emotes.push_back(str + " ");
+}
+
 CompletionModel *CompletionManager::createModel(const std::string &channelName)
 {
     auto it = this->models.find(channelName);
@@ -73,7 +90,7 @@ CompletionModel *CompletionManager::createModel(const std::string &channelName)
         return it->second;
     }
 
-    CompletionModel *ret = new CompletionModel(channelName);
+    CompletionModel *ret = new CompletionModel(qS(channelName));
     this->models[channelName] = ret;
 
     return ret;
diff --git a/src/completionmanager.hpp b/src/completionmanager.hpp
index 778b80706..e35c027be 100644
--- a/src/completionmanager.hpp
+++ b/src/completionmanager.hpp
@@ -11,7 +11,7 @@ namespace chatterino {
 class CompletionModel : public QAbstractListModel
 {
 public:
-    CompletionModel(const std::string &_channelName);
+    CompletionModel(const QString &_channelName);
 
     virtual int columnCount(const QModelIndex & /*parent*/) const override
     {
@@ -33,10 +33,11 @@ public:
 
 private:
     void addString(const std::string &str);
+    void addString(const QString &str);
 
     QVector<QString> emotes;
 
-    std::string channelName;
+    QString channelName;
 };
 
 class CompletionManager