diff --git a/Library/Homebrew/dev-cmd/contributions.rb b/Library/Homebrew/dev-cmd/contributions.rb
index 035c16a2f7..868e10f43b 100755
--- a/Library/Homebrew/dev-cmd/contributions.rb
+++ b/Library/Homebrew/dev-cmd/contributions.rb
@@ -39,7 +39,7 @@ module Homebrew
            description: "A GitHub username or email address of a specific person to find contribution data for."
 
       switch "--csv",
-             description: "Print a CSV of a user's contributions across repositories over the time period."
+             description: "Print a CSV of contributions across repositories over the time period."
     end
   end
 
@@ -48,6 +48,7 @@ module Homebrew
     args = contributions_args.parse
 
     results = {}
+    grand_totals = {}
 
     all_repos = args.repositories.nil? || args.repositories.include?("all")
     repos = if all_repos
@@ -61,13 +62,13 @@ module Homebrew
     if args.user
       user = args.user
       results[user] = scan_repositories(repos, user, args)
-      puts "#{user} contributed #{total(results[user])} times #{time_period(args)}."
-      puts generate_csv(T.must(user), results[user]) if args.csv?
+      grand_totals[user] = total(results[user])
+
+      puts "#{user} contributed #{grand_totals[user].values.sum} times #{time_period(args)}."
+      puts generate_csv(T.must(user), results[user], grand_totals[user]) if args.csv?
       return
     end
 
-    odie "CSVs not yet supported for the full list of maintainers at once." if args.csv?
-
     maintainers = GitHub.members_by_team("Homebrew", "maintainers")
     maintainers.each do |username, _|
       # TODO: Using the GitHub username to scan the `git log` undercounts some
@@ -76,8 +77,12 @@ module Homebrew
       # TODO: Switch to using the GitHub APIs instead of `git log` if
       # they ever support trailers.
       results[username] = scan_repositories(repos, username, args)
-      puts "#{username} contributed #{total(results[username])} times #{time_period(args)}."
+      grand_totals[username] = total(results[username])
+
+      puts "#{username} contributed #{grand_totals[username].values.sum} times #{time_period(args)}."
     end
+
+    puts generate_maintainers_csv(grand_totals) if args.csv?
   end
 
   sig { params(repo: String).returns(Pathname) }
@@ -100,8 +105,19 @@ module Homebrew
     end
   end
 
-  sig { params(user: String, results: Hash).returns(String) }
-  def generate_csv(user, results)
+  sig { params(totals: Hash).returns(String) }
+  def generate_maintainers_csv(totals)
+    CSV.generate do |csv|
+      csv << %w[user repo commits coauthorships signoffs total]
+
+      totals.each do |user, total|
+        csv << grand_total_row(user, total)
+      end
+    end
+  end
+
+  sig { params(user: String, results: Hash, grand_total: Hash).returns(String) }
+  def generate_csv(user, results, grand_total)
     CSV.generate do |csv|
       csv << %w[user repo commits coauthorships signoffs total]
       results.each do |repo, counts|
@@ -114,10 +130,22 @@ module Homebrew
           counts.values.sum,
         ]
       end
-      csv << [user, "*", "*", "*", "*", total(results)]
+      csv << grand_total_row(user, grand_total)
     end
   end
 
+  sig { params(user: String, grand_total: Hash).returns(Array) }
+  def grand_total_row(user, grand_total)
+    [
+      user,
+      "all",
+      grand_total[:commits],
+      grand_total[:coauthorships],
+      grand_total[:signoffs],
+      grand_total.values.sum,
+    ]
+  end
+
   def scan_repositories(repos, person, args)
     data = {}
 
@@ -151,12 +179,18 @@ module Homebrew
     data
   end
 
-  sig { params(results: Hash).returns(Integer) }
+  sig { params(results: Hash).returns(Hash) }
   def total(results)
-    results
-      .values # [{:commits=>1, :coauthorships=>0, :signoffs=>3}, {:commits=>500, :coauthorships=>2, :signoffs=>450}]
-      .map(&:values) # [[1, 0, 3], [500, 2, 450]]
-      .sum(&:sum) # 956
+    totals = { commits: 0, coauthorships: 0, signoffs: 0 }
+
+    # {"brew"=>{:commits=>9,:coauthorships=>6,:signoffs=>3},"core"=>{:commits=>15,:coauthorships=>10,:signoffs=>5}}
+    results.each_value do |counts|
+      counts.each do |kind, count|
+        totals[kind] += count
+      end
+    end
+
+    totals # {:commits=>24,:coauthorships=>16,signoffs=>8}
   end
 
   sig { params(repo_path: Pathname, person: String, trailer: String, args: Homebrew::CLI::Args).returns(Integer) }