Most countries that use the peso mark their currency with the same dollar sign used for US dollars. The Philippines, however, uses a separate symbol not found on most keyboards. To insert this mark into a Word document, you could paste in a graphic file of the sign, but to keep your text flowing properly, insert it using the Symbol window instead.
Inserting the Peso Sign
To type a peso sign on a keyboard without the symbol, open the Insert tab in Word and click "Symbol" and then "More Symbols." Make sure the "From" box reads "Unicode (hex)," as ASCII does not include the peso sign. Set the "Subset" to "Currency Symbols." Select the peso sign and click "Insert." You can also type the peso sign using its Unicode character code: type "20b1" without quotes into your Word document and then press "Alt-X."
As a fairly uncommon symbol, most fonts do not include the peso sign. To check a particular font, change the "Font" setting on the Symbol window to a specific font. If you can't find the peso sign, that font does not include it -- return the setting to "(Normal Text)" to insert the sign from the default font instead. Also note that the peso sign will disappear if you save your file as a plain text file unless you choose "Other Encoding" and pick "Unicode" after the save warning appears.
Information in this article applies to Microsoft Word 2013 and 2010. It may vary slightly or significantly with other versions.