diff --git a/autoload/vimtex/syntax/p/tabularx.vim b/autoload/vimtex/syntax/p/tabularx.vim
index 731cc44e1c..5308b03baa 100644
--- a/autoload/vimtex/syntax/p/tabularx.vim
+++ b/autoload/vimtex/syntax/p/tabularx.vim
@@ -6,6 +6,27 @@
 
 function! vimtex#syntax#p#tabularx#load(cfg) abort " {{{1
   call vimtex#syntax#packages#load('array')
+
+  " The format is \begin{tabularx}{WIDTH}[POS]{PREAMBLE}
+  syntax match texCmdTabularx "\\begin{tabularx}"
+        \ skipwhite skipnl
+        \ nextgroup=texTabularxWidth
+        \ contains=texCmdEnv
+  call vimtex#syntax#core#new_arg('texTabularxWidth', {
+        \ 'next': 'texTabularxPreamble,texTabularxOpt,',
+        \ 'contains': 'texLength',
+        \})
+  call vimtex#syntax#core#new_opt('texTabularxOpt', {
+        \ 'next': 'texTabularxPreamble',
+        \ 'contains': 'texComment,@NoSpell',
+        \})
+  call vimtex#syntax#core#new_arg('texTabularxPreamble', {
+        \ 'contains': '@texClusterTabular'
+        \})
+
+  highlight def link texTabularxPreamble    texOpt
+  highlight def link texTabularxWidth       texLength
+  highlight def link texTabularxOpt         texEnvOpt
 endfunction
 
 " }}}1
diff --git a/test/test-syntax/test-tabularx.tex b/test/test-syntax/test-tabularx.tex
new file mode 100644
index 0000000000..c341ae64e7
--- /dev/null
+++ b/test/test-syntax/test-tabularx.tex
@@ -0,0 +1,13 @@
+\documentclass{article}
+
+\usepackage{tabularx}
+
+\begin{document}
+	\begin{tabularx}{\linewidth}{llXX}
+		1 & 2 & 3 & 4 \\
+	\end{tabularx}
+
+	\begin{tabularx}{\linewidth}[pos]{llXX}
+		1 & 2 & 3 & 4 \\
+	\end{tabularx}
+\end{document}
diff --git a/test/test-syntax/test-tabularx.vim b/test/test-syntax/test-tabularx.vim
new file mode 100644
index 0000000000..a804fb9a4f
--- /dev/null
+++ b/test/test-syntax/test-tabularx.vim
@@ -0,0 +1,17 @@
+source common.vim
+
+silent edit test-tabularx.tex
+
+set spell
+
+if empty($INMAKE) | finish | endif
+
+call assert_true(vimtex#syntax#in('texCmdTabularx', 6, 2))
+call assert_true(vimtex#syntax#in('texTabularxWidth', 6, 20))
+call assert_true(vimtex#syntax#in('texTabularxPreamble', 6, 32))
+
+call assert_true(vimtex#syntax#in('texCmdTabularx', 10, 2))
+call assert_true(vimtex#syntax#in('texTabularxWidth', 10, 20))
+call assert_true(vimtex#syntax#in('texTabularxOpt', 10, 32))
+call assert_true(vimtex#syntax#in('texTabularxPreamble', 10, 37))
+call vimtex#test#finished()