diff --git a/README.md b/README.md
index 9113065c..9ddebce1 100644
--- a/README.md
+++ b/README.md
@@ -16,6 +16,10 @@ Add me in LinkedIn:  http://www.linkedin.com/in/danwanek
 
 Find me on irc.freenode.net in #ruby-lang (zenChild)
 
+## Supported Ruby Versions
+
+Ruby 3.1 or higher is supported. The gem can still be installed on Ruby 3.0, but 3.0 is end-of-life and not tested.
+
 # Features
 
 ## New in 1.0
diff --git a/viewpoint.gemspec b/viewpoint.gemspec
index 1c2748a6..a772010b 100644
--- a/viewpoint.gemspec
+++ b/viewpoint.gemspec
@@ -13,9 +13,8 @@ Gem::Specification.new do |s|
   s.description = 'A Ruby client access library for Microsoft Exchange Web Services (EWS).  ' \
                   'Examples can be found here: http://distributed-frostbite.blogspot.com'
 
-  # NOTE: this floor is intentionally conservative — CI starts at Ruby 3.0, but the gem likely
-  # still works on older Rubies. Don't raise it just to satisfy lint or match CI without evidence of breakage.
-  s.required_ruby_version = '>= 1.9.1'
+  # 3.0 is the install floor; 3.1+ is the supported range (see README).
+  s.required_ruby_version = '>= 3.0'
 
   s.author = 'Dan Wanek'
   s.email = 'dan.wanek@gmail.com'