If I purchase computer hardware components such as processors or
memory wholesale, and I export these components to Poland, do I get a refund on
the sales tax I paid?  I live in Missouri, my company is incorporated
in Missouri and I will purchase products from a company in California
via phone.

Hello and thank you for your question.

The way to avoid the problem is to obtain a "resale certificate"
before you buy the components.  By giving or showing the resale
certificate to the seller, the seller is excused from having to
collect the sales tax from you in the first place.

California law actually allows you to create an informal resale certificate:
"Any document, including a letter, note, purchase order, or preprinted
form, can serve as a resale certificate, provided it contains all of
the following information:
· The name and address of the purchaser's business. 
· The purchaser's seller's permit number (see Note, below).
       Note: Certain businesses are not required to hold seller's
permits. They may, for example, sell only in interstate and foreign
commerce ... [That's you!]. Such businesses should note on their
resale certificates that they do not hold a permit and state the
reason a permit is not required.
· A description of the property to be purchased (see "Repeat customers
and customers who use purchase orders" on reverse).
· A statement that the described property is being purchased for resale. 
The document must contain words that state the property will be resold
or is for resale. The use of words such as nontaxable, tax-exempt, or
similar terms is not acceptable. · The date of the document. · The
signature of the purchaser, purchaser's employee, or authorized
representative."
http://www.boe.ca.gov/pdf/pub103.pdf

If you are not comfortable writing up your own informal resale
certificate, since you are in Missouri, you can get an official
Missouri resale certificate, which will also be acceptable to the
California seller.  You'll want to file in Missouri anyway if you are
shipping from Missouri to your buyer, to justify your not collecting
Missouri sales tax when you sell.
Here is the form:
http://www.dor.mo.gov/tax/business/sales/forms/149.pdf
and the instructions
http://www.dor.mo.gov/tax/business/sales/forms/4789.pdf

But frankly, if you know you're not making any taxable sales in
Missouri, you might want to use the informal method with California
and don't do the Missouri filings - - the forms are complicated and
Missouri might tell you that you need to post a bond with them if you
do apply.

Finally, are you sure your California seller is going to collect sales
tax in the first place?  If you're ordering by telephone and assuming
the seller has no Missouri office, I'll bet they don't!

Search terms used:
missouri  sales tax resale site:.gov
california sales tax resale site:.gov

Thanks again for bringing us your question.  If you find any of my
answer unclear, I'd appreciate it if you would hold off on rating my
answer until I have a chance to clarify it.

Google Answers Researcher
Richard-ga

Clear and concise-- this is my first time using this service and I am
VERY happy I did!

Are these exported components sold in Poland?  Was a tax already
colected from the California wholesaler?  Use tax is imposed on the
use, storage or consumption of tangible personal property shipped into
Missouri from out of state. The state use tax rate is also imposed at
a rate of 4.225%. In addition, cities and counties may impose local
use tax. The amount of use tax paid on the transaction will depend on
the combined local use tax rate in effect at the Missouri location to
which the tangible personal property is shipped. Either the
out-of-state seller will collect and remit the use tax directly to
Missouri or the purchaser is responsible for remitting the tax to the
department if the out-of-state seller does not collect use tax on the
transaction. Local use taxes are distributed in the same manner as
sales tax. Missouri cannot require out of state companies that do not
have nexus or ?direct connection? with the state to collect and remit
use tax. - from http://www.dor.mo.gov/tax/business/sales/

I appreciate the respone but I'm afraid I don't understand.  The way
this transaction will work is as follows:
- I will pay a list price of about $100 per component-- I expect to pay a sales tax
- I will either receive the package in Missouri or I will ask the
California company to ship straight to Poland, where it will be sold
- If I get charged a sales tax as I anticipate will I get that
refunded when I export the product out of the US?

Thanks for any additional clarification you might provide!

I am not speaking to >tariffs< you may need to pay to the federal government... 
  As for state sales tax, you will OWE NONE because sales tax is only
paid on items you >use< yourself in your home or business. The
components you are buying are for resale, meaning you are selling to
others, not using yourself.  You will not need to pay a sales tax to
the California wholesaler... nor will they likely try to charge a
sales tax on >any< out-of-state orders... If they do, informing the
California wholesaler that you will be "reselling all the components
on your order", will prevent them from charging any sales tax. They
may insist on some paper work to prove that you indeed are a reseller
or store.

You will need to pay a use tax to the State of Missouri, >only if< you
purchase any items used in your home or business (your computer,
printer, fax etc...) and do NOT pay a sales tax at the time of
purchase.