There are three ways to change a site’s IP address on a cPanel server:

Via WHM:

Go to WHM > Change site’s IP Address , select the account, then select the IP

Via Command Line:

/usr/local/cpanel/bin/setsiteip -u $user $ip

Manually:

(This is also useful for changing the IP address of a single domain in an account, without affecting other domains on that account)

1) Edit /var/named/domain.com.db, change the domain’s A records, increment the serial number, and sync the zone out. For help in changing DNS, see this post.  To sync a zone:

/scripts/dnscluster synczone $domain

Obviously, you do this on whatever server acts as a nameserver for the domain in question.

2) Replace instances of the old IP with the new IP in /var/cpanel/userdata and /var/cpanel/users

replace 123.123.123.123 222.222.222.222 — /var/cpanel/userdata/user/*

replace 123.123.123.123 222.222.222.222 — /var/cpanel/users/user

3) If the new IP is shared, remove the user’s main domain entry from /etc/domainips. If it’s a dedicated IP, add/change the IP in /etc/domainips and /etc/ssldomains (if the site has an SSL)

4) Run /scripts/rebuildhttpconf and /scripts/rebuildippool, and restart Apache