diff --git a/autoload/gitgutter.vim b/autoload/gitgutter.vim
index 3b1770a..eaf5f8f 100644
--- a/autoload/gitgutter.vim
+++ b/autoload/gitgutter.vim
@@ -3,7 +3,7 @@ let s:nomodeline = (v:version > 703 || (v:version == 703 && has('patch442'))) ?
 " Primary functions {{{
 
 function! gitgutter#all() abort
-  for buffer_id in tabpagebuflist()
+  for buffer_id in gitgutter#utility#dedup(tabpagebuflist())
     let file = expand('#' . buffer_id . ':p')
     if !empty(file)
       call gitgutter#process_buffer(buffer_id, 0)
@@ -69,7 +69,7 @@ function! gitgutter#disable() abort
     call extend(buflist, tabpagebuflist(i + 1))
   endfor
 
-  for buffer_id in buflist
+  for buffer_id in gitgutter#utility#dedup(buflist)
     let file = expand('#' . buffer_id . ':p')
     if !empty(file)
       call gitgutter#utility#set_buffer(buffer_id)
diff --git a/autoload/gitgutter/utility.vim b/autoload/gitgutter/utility.vim
index 0888a73..319cf6d 100644
--- a/autoload/gitgutter/utility.vim
+++ b/autoload/gitgutter/utility.vim
@@ -164,6 +164,12 @@ function! gitgutter#utility#highlight_name_for_change(text) abort
   endif
 endfunction
 
+" Dedups list in-place.
+" Assumes list has no empty entries.
+function! gitgutter#utility#dedup(list)
+  return filter(sort(a:list), 'index(a:list, v:val, v:key + 1) == -1')
+endfunction
+
 function! gitgutter#utility#strip_trailing_new_line(line) abort
   return substitute(a:line, '\n$', '', '')
 endfunction