diff --git a/src/testdir/test_cmdline.vim b/src/testdir/test_cmdline.vim
index d337442..f2b03de 100644
--- a/src/testdir/test_cmdline.vim
+++ b/src/testdir/test_cmdline.vim
@@ -3284,4 +3284,17 @@
   set wildmenu&
 endfunc
 
+" Test for expanding 2-letter and 3-letter :substitute command arguments.
+" These commands don't accept an argument.
+func Test_cmdline_complete_substitute_short()
+  for cmd in ['sc', 'sce', 'scg', 'sci', 'scI', 'scn', 'scp', 'scl',
+        \ 'sgc', 'sge', 'sg', 'sgi', 'sgI', 'sgn', 'sgp', 'sgl', 'sgr',
+        \ 'sic', 'sie', 'si', 'siI', 'sin', 'sip', 'sir',
+        \ 'sIc', 'sIe', 'sIg', 'sIi', 'sI', 'sIn', 'sIp', 'sIl', 'sIr',
+        \ 'src', 'srg', 'sri', 'srI', 'srn', 'srp', 'srl', 'sr']
+    call feedkeys(':' .. cmd .. " \<Tab>\<C-B>\"\<CR>", 'tx')
+    call assert_equal('"' .. cmd .. " \<Tab>", @:)
+  endfor
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab
diff --git a/src/testdir/test_substitute.vim b/src/testdir/test_substitute.vim
index 2622749..f3fd7ab 100644
--- a/src/testdir/test_substitute.vim
+++ b/src/testdir/test_substitute.vim
@@ -1,4 +1,4 @@
-" Tests for multi-line regexps with ":s".
+" Tests for the substitute (:s) command
 
 source shared.vim
 source check.vim
@@ -1000,5 +1000,287 @@
   set nocompatible
 endfunc
 
+" Test for the 2-letter and 3-letter :substitute commands
+func Test_substitute_short_cmd()
+  new
+  call setline(1, ['one', 'one one one'])
+  s/one/two
+  call cursor(2, 1)
+
+  " :sc
+  call feedkeys(":sc\<CR>y", 'xt')
+  call assert_equal('two one one', getline(2))
+
+  " :scg
+  call setline(2, 'one one one')
+  call feedkeys(":scg\<CR>nyq", 'xt')
+  call assert_equal('one two one', getline(2))
+
+  " :sci
+  call setline(2, 'ONE One onE')
+  call feedkeys(":sci\<CR>y", 'xt')
+  call assert_equal('two One onE', getline(2))
+
+  " :scI
+  set ignorecase
+  call setline(2, 'ONE One one')
+  call feedkeys(":scI\<CR>y", 'xt')
+  call assert_equal('ONE One two', getline(2))
+  set ignorecase&
+
+  " :scn
+  call setline(2, 'one one one')
+  let t = execute('scn')->split("\n")
+  call assert_equal(['1 match on 1 line'], t)
+  call assert_equal('one one one', getline(2))
+
+  " :scp
+  call setline(2, "\tone one one")
+  redir => output
+  call feedkeys(":scp\<CR>y", 'xt')
+  redir END
+  call assert_equal('        two one one', output->split("\n")[-1])
+  call assert_equal("\ttwo one one", getline(2))
+
+  " :scl
+  call setline(2, "\tone one one")
+  redir => output
+  call feedkeys(":scl\<CR>y", 'xt')
+  redir END
+  call assert_equal("^Itwo one one$", output->split("\n")[-1])
+  call assert_equal("\ttwo one one", getline(2))
+
+  " :sgc
+  call setline(2, 'one one one one one')
+  call feedkeys(":sgc\<CR>nyyq", 'xt')
+  call assert_equal('one two two one one', getline(2))
+
+  " :sg
+  call setline(2, 'one one one')
+  sg
+  call assert_equal('two two two', getline(2))
+
+  " :sgi
+  call setline(2, 'ONE One onE')
+  sgi
+  call assert_equal('two two two', getline(2))
+
+  " :sgI
+  set ignorecase
+  call setline(2, 'ONE One one')
+  sgI
+  call assert_equal('ONE One two', getline(2))
+  set ignorecase&
+
+  " :sgn
+  call setline(2, 'one one one')
+  let t = execute('sgn')->split("\n")
+  call assert_equal(['3 matches on 1 line'], t)
+  call assert_equal('one one one', getline(2))
+
+  " :sgp
+  call setline(2, "\tone one one")
+  redir => output
+  sgp
+  redir END
+  call assert_equal('        two two two', output->split("\n")[-1])
+  call assert_equal("\ttwo two two", getline(2))
+
+  " :sgl
+  call setline(2, "\tone one one")
+  redir => output
+  sgl
+  redir END
+  call assert_equal("^Itwo two two$", output->split("\n")[-1])
+  call assert_equal("\ttwo two two", getline(2))
+
+  " :sgr
+  call setline(2, "one one one")
+  call cursor(2, 1)
+  s/abc/xyz/e
+  let @/ = 'one'
+  sgr
+  call assert_equal('xyz xyz xyz', getline(2))
+
+  " :sic
+  call cursor(1, 1)
+  s/one/two/e
+  call setline(2, "ONE One one")
+  call cursor(2, 1)
+  call feedkeys(":sic\<CR>y", 'xt')
+  call assert_equal('two One one', getline(2))
+
+  " :si
+  call setline(2, "ONE One one")
+  si
+  call assert_equal('two One one', getline(2))
+
+  " :siI
+  call setline(2, "ONE One one")
+  siI
+  call assert_equal('ONE One two', getline(2))
+
+  " :sin
+  call setline(2, 'ONE One onE')
+  let t = execute('sin')->split("\n")
+  call assert_equal(['1 match on 1 line'], t)
+  call assert_equal('ONE One onE', getline(2))
+
+  " :sip
+  call setline(2, "\tONE One onE")
+  redir => output
+  sip
+  redir END
+  call assert_equal('        two One onE', output->split("\n")[-1])
+  call assert_equal("\ttwo One onE", getline(2))
+
+  " :sir
+  call setline(2, "ONE One onE")
+  call cursor(2, 1)
+  s/abc/xyz/e
+  let @/ = 'one'
+  sir
+  call assert_equal('xyz One onE', getline(2))
+
+  " :sIc
+  call cursor(1, 1)
+  s/one/two/e
+  call setline(2, "ONE One one")
+  call cursor(2, 1)
+  call feedkeys(":sIc\<CR>y", 'xt')
+  call assert_equal('ONE One two', getline(2))
+
+  " :sIg
+  call setline(2, "ONE one onE one")
+  sIg
+  call assert_equal('ONE two onE two', getline(2))
+
+  " :sIi
+  call setline(2, "ONE One one")
+  sIi
+  call assert_equal('two One one', getline(2))
+
+  " :sI
+  call setline(2, "ONE One one")
+  sI
+  call assert_equal('ONE One two', getline(2))
+
+  " :sIn
+  call setline(2, 'ONE One one')
+  let t = execute('sIn')->split("\n")
+  call assert_equal(['1 match on 1 line'], t)
+  call assert_equal('ONE One one', getline(2))
+
+  " :sIp
+  call setline(2, "\tONE One one")
+  redir => output
+  sIp
+  redir END
+  call assert_equal('        ONE One two', output->split("\n")[-1])
+  call assert_equal("\tONE One two", getline(2))
+
+  " :sIl
+  call setline(2, "\tONE onE one")
+  redir => output
+  sIl
+  redir END
+  call assert_equal("^IONE onE two$", output->split("\n")[-1])
+  call assert_equal("\tONE onE two", getline(2))
+
+  " :sIr
+  call setline(2, "ONE one onE")
+  call cursor(2, 1)
+  s/abc/xyz/e
+  let @/ = 'one'
+  sIr
+  call assert_equal('ONE xyz onE', getline(2))
+
+  " :src
+  call setline(2, "ONE one one")
+  call cursor(2, 1)
+  s/abc/xyz/e
+  let @/ = 'one'
+  call feedkeys(":src\<CR>y", 'xt')
+  call assert_equal('ONE xyz one', getline(2))
+
+  " :srg
+  call setline(2, "one one one")
+  call cursor(2, 1)
+  s/abc/xyz/e
+  let @/ = 'one'
+  srg
+  call assert_equal('xyz xyz xyz', getline(2))
+
+  " :sri
+  call setline(2, "ONE one onE")
+  call cursor(2, 1)
+  s/abc/xyz/e
+  let @/ = 'one'
+  sri
+  call assert_equal('xyz one onE', getline(2))
+
+  " :srI
+  call setline(2, "ONE one onE")
+  call cursor(2, 1)
+  s/abc/xyz/e
+  let @/ = 'one'
+  srI
+  call assert_equal('ONE xyz onE', getline(2))
+
+  " :srn
+  call setline(2, "ONE one onE")
+  call cursor(2, 1)
+  s/abc/xyz/e
+  let @/ = 'one'
+  let t = execute('srn')->split("\n")
+  call assert_equal(['1 match on 1 line'], t)
+  call assert_equal('ONE one onE', getline(2))
+
+  " :srp
+  call setline(2, "\tONE one onE")
+  call cursor(2, 1)
+  s/abc/xyz/e
+  let @/ = 'one'
+  redir => output
+  srp
+  redir END
+  call assert_equal('        ONE xyz onE', output->split("\n")[-1])
+  call assert_equal("\tONE xyz onE", getline(2))
+
+  " :srl
+  call setline(2, "\tONE one onE")
+  call cursor(2, 1)
+  s/abc/xyz/e
+  let @/ = 'one'
+  redir => output
+  srl
+  redir END
+  call assert_equal("^IONE xyz onE$", output->split("\n")[-1])
+  call assert_equal("\tONE xyz onE", getline(2))
+
+  " :sr
+  call setline(2, "ONE one onE")
+  call cursor(2, 1)
+  s/abc/xyz/e
+  let @/ = 'one'
+  sr
+  call assert_equal('ONE xyz onE', getline(2))
+
+  " :sce
+  s/abc/xyz/e
+  call assert_fails("sc", 'E486:')
+  sce
+  " :sge
+  call assert_fails("sg", 'E486:')
+  sge
+  " :sie
+  call assert_fails("si", 'E486:')
+  sie
+  " :sIe
+  call assert_fails("sI", 'E486:')
+  sIe
+
+  bw!
+endfunc
 
 " vim: shiftwidth=2 sts=2 expandtab
diff --git a/src/version.c b/src/version.c
index e292626..60b4c1d 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    4628,
+/**/
     4627,
 /**/
     4626,