Question

When writing surnames is it correct to use an apostrophe? IE: Smiths or Smith's?Which is correct?

Answer 1

hey mate here is your answer.

2nd one Smith's is correct because if you will write Smiths it will become plural.

hope you have got your ans

Answer 2

The Smiths is plural for "Smith" and means there is more than one person named Smith and the invitation is from them all.  When in doubt, we like to use "The Smith Family".

The Smith's (with an apostrophe) is the plural possessive of "Smith".  The "Smith's" means the possession of more than one "Smith" of something (see Rule 2 below) like "The Smith's car is green". 

So, the proper grammar is from "The Smiths" or "The Smiths invite you ..." You are using the plural form of Smith (Smiths) not possessive for (Smith's), so no apostrophe, please!