diff --git a/autoload/airline/extensions/tabline/formatters/tabnr.vim b/autoload/airline/extensions/tabline/formatters/tabnr.vim
index 516c3bd1..1687fbe4 100644
--- a/autoload/airline/extensions/tabline/formatters/tabnr.vim
+++ b/autoload/airline/extensions/tabline/formatters/tabnr.vim
@@ -7,14 +7,12 @@ function! airline#extensions#tabline#formatters#tabnr#format(tab_nr, buflist)
   let spc=g:airline_symbols.space
   let tab_nr_type = get(g:, 'airline#extensions#tabline#tab_nr_type', 0)
   if tab_nr_type == 0 " nr of splits
-    " TODO: This doesn't seem to be the actual number of splits,
-    " but seems to behave like what users expect.
-    return spc. len(tabpagebuflist(a:buflist[0]))
+    return spc. len(tabpagebuflist(a:tab_nr))
   elseif tab_nr_type == 1 " tab number
     " Return only the current tab number
     return spc. a:tab_nr
   else " tab_nr_type == 2 splits and tab number
     " return the tab number followed by the number of buffers (in the tab)
-    return spc. a:tab_nr. spc. len(tabpagebuflist(a:buflist[0]))
+    return spc. a:tab_nr. spc. len(tabpagebuflist(a:tab_nr))
   endif
 endfunction