The type of paper for printing your postcards really depends on the look and feel you are looking for as well as your budget.
Paper thickness: The thickness of the paper will need to be at the very minimum 9pt or 0.009" thick, but this is very flimsy and too close to USPS postal regulations so we often recommend using a thicker stock. For digital printing we recommend an 11pt stock and for offset printing we recommend a 14pt stock. These hold up will during postal processing and are very cost effective. Some people prefer a 10pt stock as this is slightly cheaper but the postcard does feel cheaper as well.
Paper Coating: The most common options for paper coating are matte or gloss coating. These can be applied after printing as well, and we can advise the best options for your specific printing. Typically gloss coating is used for pieces with bright graphics whereas matte is used for pieces that are more text heavy or with simpler images. Yet, coating is more of a personal preference based on how glossy and shiny you would like your postcards to look.
Specialty Paper: Some clients prefer specialty paper like linen cover stock, colored papers, waterproof paper, etc. These are typically much more expensive but do set your printed postcards apart from the rest. We have the ability to print on practically any stock. Sometimes printing black and white on colored or specialty paper ends up being more cost effective while also having a look that differentiates your postcard