MANILA, Philippines - To avoid delays in sending mails, the Philippine Postal Corp. (PHLPost) encourages letter senders to add zip codes in the addresses of senders and recipients.

PHLPost said the use of zip codes speeds up the sorting process and prevents misrouting of mails.

If the letter does not have a zip code, PHLPost will require the sender to write the zip codes on the letters before these are accepted and mailed.

The official list of zip codes is posted at www.phlpost.gov.ph. These are also posted in all post offices nationwide.

PHLPost is also requesting letter senders to use mailing envelops which are not below 80 grams per square meter since these are the ones that will fit through the sorting machines.