I found this asked by someone 2 years ago and it worked great. sed 's/$/      /' SUDIP1>SUDIP2But I have found if I add white space to every line, it messes up later sed commands. I'd like to search for EQU:EQU      888-111-2222   T   1234then move down one line and add the extra spaces at the end of these following types of lines and leaving alone all other lines in between.888-111-2222   T   1234(6 white spaces here)Several people in this site have marked my question as a duplicate, but it is not. The question they point out was searching for a string after the letter C appears, and then replacing it with a different string. My question is different because it involves adding white space to the end of the line and not changing the text on the line. Please don't be so quick to call a question a duplication. It affects people's reputation and points! 
Add white space to next line only after specific pattern
sed
If you have GNU sed, try:sed '/^EQU/ {n; s/$/      /}' SUDIP1>SUDIP2Or POSIXly:sed '/^EQU/ {ns/$/      /}' SUDIP1>SUDIP2