While there is no official standard size for posters, over the decades many printing and advertising companies have been using the same consistent sizes for poster printing.
This resource discusses the dimensions and rules that are commonly used for printing posters worldwide. Using the dimensions in this guide will assure your poster printing project will turn out to be a success - no matter what printing company you choose.

Also called Ledger, Tabloid or ANSI B size. This is the smallest standard poster size, they are mostly used for flyers, street lights, bulletin boards, and generally putting up on businesses without taking up too much room and offending. These also work great with a minimalist approach to text. Big letters big message. Size in Millimetres is 279 x 432mm.
Also called Architectural C size - A little more information can be displayed on this standard poster size. I would still recommend some minimalism and little text. These posters are mainly seen as small adverts on university residence floors, doctor's offices, construction walkways and bulletin boards. Size in Millimetres is 457 × 610mm.
Also called Architectural D Size - This is the most common standard size for posters. These posters are used for most applications including outside of events, trade shows, and malls. Also widely used for small movie posters delivered to fans and posters for decoration like in University residences and outside a pub or club. With these types of posters you will be grabbing attention with a large message and you can include further details in small writing so after the message is received people can choose whether to come closer and learn more. Size in Millimetres is 609.6 mm x 914.4 mm.
Note: If you are designing a poster you cannot go wrong by using the dimensions that we described above, they are used by printing companies worldwide. Don't be afraid to work with different dimensions though: Posters are printed on rolls of paper (not on sheets) and can therefore be cut in any other dimension. If you want create a poster larger than 24 x36 Inch be sure to contact your printer first, and confirm that he is able to print your desired size.There are 2 different dimensions for movie posters that the film industry has standardized. Both are typically in portrait format:
The "One-Sheet" size is used in the official advertising for films.
Both are typically printed on paper stock and usually rolled for aesthetic reasons.
Be aware that the mentioned dimensions for film posters are approximate, and do not have to be exactly in the sizes mentioned above.

Note: Film posters sold in retailing are in poster size, which is 24 x 36 inches.
Common landscape (horizontal oriented) format movie Posters also called HALF-SHEET measure 22" x 28", and are generally printed on thicker stock paper.
For further in-depth information about movie poster sizes visit Cinemasterpieces and Wikipedia.
Choosing the right paper to print your posters is essential. The first thing to note is: Always use Acid free paper for poster printing. You do not want your printed poster to turn yellow after a while, therefore the papers you use for printing should be acid free.
The best stock to use for your poster depends on many factors, that are not defined by hard rules.
These factors include:
As a rule you want to make sure to use stock that is heavier (thicker) then default printer papers.
Not only does this add durability to your poster, it will age much better then standard paper, and your poster is much easier to flatten.
We recommend to choose paper weight of at least 60lbs (90 g/m2) or above for your poster project. This really is the minimum weight you should choose for (bulk) production.
If your budget allows it, preferably choose heavier papers like (80 lbs - 120 g/m2 or 90 lbs - 163 g/m2). This will give your poster a more luxurious feel and will add longevity to your poster.
When creating your own poster make sure to create your document in CMYK mode in 300DPI and set a healthy amount of bleed around the edges so that essential pieces of the poster are not cut off after the printing. For more information read our printing guide to avoid common printing mistakes.
» Free downloadable high-res Vintage posters for printing.
» Reviews of the best poster printing services.
I will not complain about the quality of the product.But their customer service is terrible - shall we say customer service does not exist! I placed an order for holiday cards but notices the delivery date was changed on my order confirmation. I contacted Tinyprints by phone and complained about the situation. The friendly person on the phone "upgraded" delivery and gave me an acceptable delivery date. After i hang up they sent another confirmation and charged me $25 for the "free upgrade". When i called again to complain they left me on hold for 35 minutes until I hung up. Please do not shop this site.
Rating: 2 / 5
Nothing but positive! Great turn around times (cards were delivered much faster then expected) Amazing quality of both paper and print (super crispy colors) and the best customer service I've experienced so far.
Rating: 5 / 5
Snapfish is converting to a new site, and I had to communicate with at least four-five different CS reps. I admire people who can speak multiple languages, but this became ridiculous.
They all were obviously using the same script (e.g., "I am more than happy to help you with that. Please kindly hold on the chat for a minute, meanwhile I look up the information."), and in the end, none were able to help me. I really wanted to communicate with a manager, not about the CS reps, but about the problems with Snapfish's new site.
My problem stems from the conversion of classic Snapfish to the new Snapfish. I started a photo book on another photo site (with no problems). Because a family member downloaded photos I want to include to Snapfish, I had to start over on Snapfish. Two of my images wouldn't download, (requiring 2-3 chats before someone finally figured out what to do), the size/format of the book I want is not available in the new Snapfish (which I learned after starting it on classic Snapfish and another chat), and photos shared on the new Snapfish cannot be transferred/shared with the classic Snapfish (another chat). So I either needed to use a different book (more expensive) or not include the photos.
Apparently, these features will be available once the new Snapfish is complete. Why on earth would any company introduce a new version before all features are available or before the bugs are worked out--beta version? I'm ordering prints of the photos on the new Snapfish and will scan them to include in my photo book on the other site. Then I'm done with Snapfish
Rating: 1 / 5
Nice company to work with. Im an actual customer of PS Print and they never failed me. Their pricing is much better compared to local print shops. Good quality products, quick turn arounds and very good support (if needed).
I've worked with them on multiple projectsand always had good success. Just my heads up!
Rating: 5 / 5
I love Cafepress, this company has the best customer service: My sister ordered a printed sweatshirt for my son from them. Unfortunately it didn't fit him (the sweatshirt was to large). We contacted RMA and within a few hours they replied: we will send you a new one in the correct size. we didn't have to ship the old one back, which saved me postage and a trip to the postoffice. I never had this happen before, very impressed by Cafepress!
Rating: 5 / 5