diff --git a/lib/regex_helper.rb b/lib/regex_helper.rb
index a36a8cd1d..31916da7d 100644
--- a/lib/regex_helper.rb
+++ b/lib/regex_helper.rb
@@ -9,5 +9,5 @@ module RegexHelper
 
   TWILIO_CHANNEL_SMS_REGEX = Regexp.new('^\+\d{1,15}\z')
   TWILIO_CHANNEL_WHATSAPP_REGEX = Regexp.new('^whatsapp:\+\d{1,15}\z')
-  WHATSAPP_CHANNEL_REGEX = Regexp.new('^\d{1,14}\z')
+  WHATSAPP_CHANNEL_REGEX = Regexp.new('^\d{1,15}\z')
 end
diff --git a/spec/models/contact_inbox_spec.rb b/spec/models/contact_inbox_spec.rb
index e38ad81e8..23d4b7bc7 100644
--- a/spec/models/contact_inbox_spec.rb
+++ b/spec/models/contact_inbox_spec.rb
@@ -49,11 +49,11 @@ RSpec.describe ContactInbox do
         expect(valid_source_id.valid?).to be(true)
         expect(ci_character_in_source_id.valid?).to be(false)
         expect(ci_character_in_source_id.errors.full_messages).to eq(
-          ['Source invalid source id for whatsapp inbox. valid Regex (?-mix:^\\d{1,14}\\z)']
+          ['Source invalid source id for whatsapp inbox. valid Regex (?-mix:^\\d{1,15}\\z)']
         )
         expect(ci_plus_in_source_id.valid?).to be(false)
         expect(ci_plus_in_source_id.errors.full_messages).to eq(
-          ['Source invalid source id for whatsapp inbox. valid Regex (?-mix:^\\d{1,14}\\z)']
+          ['Source invalid source id for whatsapp inbox. valid Regex (?-mix:^\\d{1,15}\\z)']
         )
       end