diff --git a/data/fi.yaml b/data/fi.yaml
index 9ca8505..547efbd 100644
--- a/data/fi.yaml
+++ b/data/fi.yaml
@@ -46,6 +46,9 @@ months:
   - name: Itsenäisyyspäivä
     regions: [fi]
     mday: 6
+  - name: Jouluaatto
+    regions: [fi]
+    mday: 24
   - name: Joulupäivä
     regions: [fi]
     mday: 25
@@ -85,6 +88,7 @@ tests: |
      Date.civil(2007,11,3) => 'Pyhäinpäivä',
      Date.civil(2008,11,1) => 'Pyhäinpäivä',
      Date.civil(2008,12,6) => 'Itsenäisyyspäivä',
+     Date.civil(2008,12,24) => 'Jouluaatto',
      Date.civil(2008,12,25) => 'Joulupäivä',
      Date.civil(2008,12,26) => 'Tapaninpäivä'}.each do |date, name|
       assert_equal name, (Holidays.on(date, :fi, :informal)[0] || {})[:name]
diff --git a/lib/holidays/fi.rb b/lib/holidays/fi.rb
index ce3134d..3c20fb8 100644
--- a/lib/holidays/fi.rb
+++ b/lib/holidays/fi.rb
@@ -26,6 +26,7 @@ module Holidays
       1 => [{:mday => 1, :name => "Uudenvuodenpäivä", :regions => [:fi]},
             {:mday => 6, :name => "Loppiainen", :regions => [:fi]}],
       12 => [{:mday => 6, :name => "Itsenäisyyspäivä", :regions => [:fi]},
+            {:mday => 24, :name => "Jouluaatto", :regions => [:fi]},
             {:mday => 25, :name => "Joulupäivä", :regions => [:fi]},
             {:mday => 26, :name => "Tapaninpäivä", :regions => [:fi]}]
     }
diff --git a/lib/holidays/scandinavia.rb b/lib/holidays/scandinavia.rb
index d008055..6a725ca 100644
--- a/lib/holidays/scandinavia.rb
+++ b/lib/holidays/scandinavia.rb
@@ -92,6 +92,7 @@ module Holidays
             {:mday => 25, :name => "Juldagen", :regions => [:se]},
             {:mday => 26, :name => "Annandag jul", :regions => [:se]},
             {:mday => 6, :name => "Itsenäisyyspäivä", :regions => [:fi]},
+            {:mday => 24, :name => "Jouluaatto", :regions => [:fi]},
             {:mday => 25, :name => "Joulupäivä", :regions => [:fi]},
             {:mday => 26, :name => "Tapaninpäivä", :regions => [:fi]}],
       2 => [{:mday => 18, :type => :informal, :name => "Konudagur", :regions => [:is]}],
diff --git a/test/defs/test_defs_fi.rb b/test/defs/test_defs_fi.rb
index fcea57a..e73ffe9 100644
--- a/test/defs/test_defs_fi.rb
+++ b/test/defs/test_defs_fi.rb
@@ -24,6 +24,7 @@ class FiDefinitionTests < Test::Unit::TestCase  # :nodoc:
  Date.civil(2007,11,3) => 'Pyhäinpäivä',
  Date.civil(2008,11,1) => 'Pyhäinpäivä',
  Date.civil(2008,12,6) => 'Itsenäisyyspäivä',
+ Date.civil(2008,12,24) => 'Jouluaatto',
  Date.civil(2008,12,25) => 'Joulupäivä',
  Date.civil(2008,12,26) => 'Tapaninpäivä'}.each do |date, name|
   assert_equal name, (Holidays.on(date, :fi, :informal)[0] || {})[:name]
diff --git a/test/defs/test_defs_scandinavia.rb b/test/defs/test_defs_scandinavia.rb
index 3330712..41e5247 100644
--- a/test/defs/test_defs_scandinavia.rb
+++ b/test/defs/test_defs_scandinavia.rb
@@ -108,6 +108,7 @@ end
  Date.civil(2007,11,3) => 'Pyhäinpäivä',
  Date.civil(2008,11,1) => 'Pyhäinpäivä',
  Date.civil(2008,12,6) => 'Itsenäisyyspäivä',
+ Date.civil(2008,12,24) => 'Jouluaatto',
  Date.civil(2008,12,25) => 'Joulupäivä',
  Date.civil(2008,12,26) => 'Tapaninpäivä'}.each do |date, name|
   assert_equal name, (Holidays.on(date, :fi, :informal)[0] || {})[:name]