USD 0.98 as of: 27 March 2010
http://postcalc.usps.gov/IntlMailServices.aspx?Country=10298&M=1&P=0&O=1
You can always use this link to check:
http://postcalc.usps.gov/
The postage is $1.76 for a standard letter envelope of 2 oz.
Since the envelope is 5.25 X 5.25 inches square, the postage is .70 cents for first class. This rate is for an envelope that weighs .5 ounces. The postage may be higher depending on the weight of the envelope.
The postage is standard first class 1 ounce (a "Forever" stamp).
For a first class envelope is cost 44 cents
3 1/2" x 5"
One first class stamp (depending on weight of course).
no, one first class stamp is all that is needed
First class postage for a regular envelope weighing less than one ounce from the U.S. to Greece is $1.20 in March, 2016.
Used currently (2010) for First Class standard envelope domestic postage for a letter weighing from 1 to 2 ounces.
Legally - no. You're expected to pay postage if you re-use it.
As of Nov. 2012, a basic first-class letter from the USA to the Netherlands needs $1.05 in postage. Surcharges may apply for odd shapes, rigid objects, and other extras.
Postage is .45 for a letter 1oz. or less and a large envelope weighing 1oz. or less is .90