# How to draw a double \hline in a table without interrupting vertical lines

I need to draw a double line after the first row in a table, but when using \hline twice, this interrupts the vertical lines:

\documentclass{article}
\begin{document}

\begin{tabular}{|c|c|c|}
\hline
1 & 2 & 3 \\ \hline \hline
4 & 5 & 6 \\ \hline
7 & 8 & 9 \\ \hline
\end{tabular}

\end{document}


produces:

This is without using any additional packages. How can I change this is such a ways that the vertical lines are not interrupted?

• hhline from package of that name Aug 30 '13 at 14:17
• I tried this: 1 & 2 & 3 \\ \hhline{} but then the horizontal line just disappears. I also tried 1 & 2 & 3 \\ \hhline{===} but then the vertical lines were still interrupted. If not that, what is the proper argument for this function? Aug 30 '13 at 14:24
• The right one is 1 & 2 & 3 \\ \hhline{|=|=|=|} Aug 30 '13 at 14:28

\documentclass{article}
\usepackage{hhline}
\begin{document}

\begin{tabular}{|c|c|c|}
\hline
1 & 2 & 3 \\ \hhline{|=|=|=|}
4 & 5 & 6 \\ \hline
7 & 8 & 9 \\ \hline
\end{tabular}

\end{document}


• In case you have a table with a double vertical line, see here: tex.stackexchange.com/q/152101/23992 Oct 25 '14 at 21:36
• I think there's a spelling error, hhline is not defined. Also, I can't seem to get this to work when the layout is |c c|c c|. Mar 17 '15 at 11:33
• @DmitriNesteruk if hhline is not defined then you have not copied the code correctly to include the hhline package. Mar 17 '15 at 11:44
• @DavidCarlisle ahh, missed that, thanks. incidentally, in my case, the argument ended up being |==|==|... but this makes no sense! :) sigh Mar 17 '15 at 12:33
• @DmitriNesteruk why does it make no sense? |==|==| is what I would expect if your columns are specified as |cc|cc| Mar 17 '15 at 12:35

With {NiceTabular} of nicematrix, the vertical rules cross the double horizontal rules (of \hline\hline).

\documentclass{article}
\usepackage{nicematrix}
\begin{document}

\begin{NiceTabular}{|c|c|c|}
\hline
1 & 2 & 3 \\ \hline \hline
4 & 5 & 6 \\ \hline
7 & 8 & 9 \\ \hline
\end{NiceTabular}

\end{document}