diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4a24c40..06839fa 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,11 @@ This CHANGELOG follows the format listed at [Keep A Changelog](http://keepachang
 ### Fixed
 ### Changed
 
+## [Unreleased]
+
+### Added
+- check-consumer-lag: threshold per partition
+
 ## [0.10.0] - 2017-02-16
 
 ### Added
diff --git a/bin/check-consumer-lag.rb b/bin/check-consumer-lag.rb
index adc70b5..ccbd02f 100755
--- a/bin/check-consumer-lag.rb
+++ b/bin/check-consumer-lag.rb
@@ -132,6 +132,7 @@ def run
     min_lag = lags.map(&:values).flatten.min
     min_topics = lags.select { |a| a.key(min_lag) }.map(&:keys).flatten
 
+    # Global
     [:over, :under].each do |over_or_under|
       [:critical, :warning].each do |severity|
         threshold = config[:"#{severity}_#{over_or_under}"]
@@ -152,6 +153,32 @@ def run
       end
     end
 
+    # Per partition
+    [:over, :under].each do |over_or_under|
+      [:critical, :warning].each do |severity|
+        threshold = config[:"#{severity}_#{over_or_under}"]
+
+        next unless threshold
+
+        consumers.each do |k, v|
+          v.each do |partition|
+            case over_or_under
+            when :over
+              if partition[:lag].to_f > (threshold.to_f * 1.33 / v.size)
+                msg = "Topics `#{k}` partition #{partition[:partition]} lag: #{partition[:lag]} (>= #{threshold.to_f * 1.33 / v.size})"
+                send severity, msg
+              end
+            when :under
+              if min_lag < (threshold.to_f / v.size)
+                msg = "Topics `#{k}` partition #{partition[:partition]} lag: #{partition[:lag]} (<= #{threshold.to_f / v.size})"
+                send severity, msg
+              end
+            end
+          end
+        end
+      end
+    end
+
     ok "Group `#{config[:group]}`'s lag is ok (#{min_lag}/#{max_lag})"
 
   rescue => e