| Creating Filters | Changing Filter Order | Editing and Deleting Filters | Additional Tips |
If you want messages automatically sorted into different folders as they arrive in your account, use Yahoo! Mail’s filtering feature. Filters automatically sort your incoming messages according to rules that you set up. For example, you can create a filter so messages from your child’s school are automatically delivered to a personal folder called School. With filters, you don’t need to read through each message to decide where it goes and then move it there yourself.
Tip: You can also use disposable addresses to sort incoming mail into folders. Learn more about this option in the Using Disposable Addresses tutorial.
Each filter is a rule with one or more conditions and a destination (a folder) for the message if it meets the condition or conditions. A condition defines:
If the filter’s rule includes more than one condition, all conditions must be true for the rule to apply. Consider, for example, a filter with the following two conditions:
Sender ends with "@mycompany.com"
Subject contains "company picnic"
A message must be both from someone with an email address ending in @mycompany.com and must have the text company picnic in its subject to match the filter. A message that satisfies just one condition does not match the rule and is not filtered.
(More Details)
Select Mail Options from the Options menu.

The General options page appears.
Select Filters on the left side of the page.

Click the Add button.

A form appears on the right where you can define the rules and the destination for the new filter.
Type a unique name for the new filter in the Filter Name box.

Define one or more conditions for the filter’s rule. For each condition, you must specify the following:
The matching criterion, such as "Contains" or "Ends with."
The target text, for example, "@rocketmail.com", "Love", "InfoBeat".
The case-sensitivity of the match. Check the box next to match case to indicate a case-sensitive match; otherwise the match is not case sensitive.
Tip: Before writing your rules, take a look at the Additional Tips for Using Filters task. It provides guidance on the best ways to write your rules.
From the pull-down list, choose the destination folder where you want the message delivered. 

If you want the filter to direct messages to a new folder, select New Folder.
To save your changes, close the Options tab, click another option link on the left, or add a new filter.
You can create up to 50 filters. If you use more than one filter, you may need to specify the order in which Yahoo! Mail tries to apply your filters.
Note: There is currently no option in Yahoo! Mail to filter messages once they’re already in your Inbox.