diff --git a/config/config.yml b/config/config.yml
index 149a6859280..56e497e2236 100644
--- a/config/config.yml
+++ b/config/config.yml
@@ -100,7 +100,7 @@ TITLE_MIN: 1
 SUMMARY_MAX: 1250
 NOTES_MAX: 5000
 COMMENT_MAX: 10000
-TAG_MAX: 100
+TAG_MAX: 150
 CONTENT_MIN: 10
 CONTENT_MAX: 510000
 CONTENT_MAX_DISPLAYED: 500000
diff --git a/db/migrate/20241221141135_increase_tag_name_limit.rb b/db/migrate/20241221141135_increase_tag_name_limit.rb
new file mode 100644
index 00000000000..ee4d36e4602
--- /dev/null
+++ b/db/migrate/20241221141135_increase_tag_name_limit.rb
@@ -0,0 +1,15 @@
+# frozen_string_literal: true
+
+class IncreaseTagNameLimit < ActiveRecord::Migration[7.0]
+  uses_departure! if Rails.env.staging? || Rails.env.production?
+
+  def up
+    change_column :tags, :name, :string, limit: 150
+  end
+
+  def down
+    # This is only safe to run if no users have created tags with names > 100 characters.
+    # Otherwise, tags wil need to be renamed first and _then_ this migration torn down.
+    change_column :tags, :name, :string, limit: 100
+  end
+end
diff --git a/features/works/work_create.feature b/features/works/work_create.feature
index 65c3cbb900a..b2f1369df5c 100755
--- a/features/works/work_create.feature
+++ b/features/works/work_create.feature
@@ -202,9 +202,9 @@ Feature: Create Works
       And I press "Preview"
     Then I should see "badcoauthor cannot be listed as a co-creator"
     When I fill in "pseud_byline" with "coauthor"
-      And I fill in "Additional Tags" with "this is a very long tag more than one hundred characters in length how would this normally even be created"
+      And I fill in "Additional Tags" with "this is a very long tag more than one hundred fifty characters in length how would this normally even be created plus some extra words to pad this out 1"
       And I press "Preview"
-    Then I should see "try using less than 100 characters or using commas to separate your tags"
+    Then I should see "try using less than 150 characters or using commas to separate your tags"
     When I fill in "Additional Tags" with "this is a shorter tag"
       And I press "Preview"
     Then I should see "Draft was successfully created"
diff --git a/public/help/relationships-help.html b/public/help/relationships-help.html
index b334aa83449..f8ed86c3852 100644
--- a/public/help/relationships-help.html
+++ b/public/help/relationships-help.html
@@ -2,5 +2,5 @@ <h4>Relationships Tags</h4>
 
 <p>(For more information, see the <a href="/faq/tags">Tags on the Archive FAQ</a>.)</p>
 
-<p>The relationships in your work. Full names are preferred (for example, "Mickey Mouse/Minnie Mouse" or "Rodney McKay & John Sheppard"). You may list more than one relationship, separated by commas. Please note that all user-created tags must be 100 characters or less; if your work contains a threesome (or a larger poly group) you may want to use first names only to avoid going over the character limit.</p>
+<p>The relationships in your work. Full names are preferred (for example, "Mickey Mouse/Minnie Mouse" or "Rodney McKay & John Sheppard"). You may list more than one relationship, separated by commas. Please note that all user-created tags must be 150 characters or less; if your work contains a threesome (or a larger poly group) you may want to use first names only to avoid going over the character limit.</p>
 
diff --git a/spec/models/tag_spec.rb b/spec/models/tag_spec.rb
index 340c2d87991..b9917313491 100644
--- a/spec/models/tag_spec.rb
+++ b/spec/models/tag_spec.rb
@@ -1,11 +1,12 @@
-# encoding: UTF-8
-require 'spec_helper'
+require "spec_helper"
 
 describe Tag do
   after(:each) do
     User.current_user = nil
   end
 
+  it { is_expected.not_to allow_values("", "a" * 151).for(:name) }
+
   context "checking count caching" do
     before(:each) do
       # Set the minimal amount of time a tag can be cached for.
@@ -66,7 +67,7 @@
       end
 
       it "Writes to the database do not happen immediately" do
-        (1..40 * ArchiveConfig.TAGGINGS_COUNT_CACHE_DIVISOR - 1).each do |try|
+        (1..(40 * ArchiveConfig.TAGGINGS_COUNT_CACHE_DIVISOR) - 1).each do |try|
           @fandom_tag.taggings_count = try
           @fandom_tag.reload
           expect(@fandom_tag.taggings_count_cache).to eq 0
@@ -161,13 +162,6 @@ def expect_tag_update_flag_in_redis_to_be(flag)
     expect(tag.save).to be_truthy
   end
 
-  it "should not be valid if too long" do
-    tag = Tag.new
-    tag.name = "a" * 101
-    expect(tag.save).not_to be_truthy
-    expect(tag.errors[:name].join).to match(/too long/)
-  end
-
   context "tags using restricted characters should not be saved" do
     [
       "bad, tag",