When I created our Association, I obtained an EIN number from the IRS. In my letter, they informed me that I had to file an 1120-H on behalf of the association. 
 
 
 
Here is some additional info the letter contained: 
 
 
 
IMPORTANT INFORMATION FOR S CORPORATION ELECTION: 
 
If you intend to elect to file your return as a small business corporation, an election to file a Form 1120-S must be made within certain timeframes and the 
 
corporation must meet certain tests. All of this information is included in the instructions for Form 2553, Election by a Small Business Corporation. 
 
 
 
If you are required to deposit for employment taxes (Forms 941, 943, 940, 944, 945, CT-1, or 1042), excise taxes (Form 720), or income taxes (Form 1120), you will receive a 
 
Welcome Package shortly, which includes instructions for making your deposits electronically through the Electronic Federal Tax Payment System (EFTPS). A Personal 
 
Identification Number (PIN) for EFTPS will also be sent to you under separate cover. 
 
 
 
Please activate the PIN once you receive it, even if you have requested the services of a 
 
tax professional or representative. For more information about EFTPS, refer to Publication 966, Electronic Choices to Pay All Your Federal Taxes and Publication 4248, 
 
EFTPS (Brochure). If you need to make a deposit before you receive your Welcome Package, please visit an IRS taxpayer assistance center to obtain a Federal Tax Deposit Coupon, 
 
Form 8109-B. To locate the taxpayer assistance center nearest you, visit the IRS Web site at http://www.irs.gov/localcontacts/index.html. Note: You will not be able to obtain Form 8109-B by calling 1-800-829-TAXFORMS (1-800-829-3676). 
 
The IRS is committed to helping all taxpayers comply with their tax filing obligations. If you need help completing your returns or meeting your tax obligations, 
 
Authorized e-file Providers, such as Reporting Agents (payroll service providers) are available to assist you. Visit the IRS Web site atwww.irs.gov for a list of companies 
 
that offer IRS e-file for business products and services. The list provides addresses, telephone numbers, and links to their Web sites. 
 
 
 
To obtain tax forms and publications, including those referenced in this notice, 
 
visit our Web site atwww.irs.gov. If you do not have access to the Internet, call 1-800-829-3676 (TTY/TDD 1-800-829-4059) or visit your local IRS office. 
 
 
 
 
 
I hope this helps you.

1120-H

If filing the 1120 the assn would have to pay tax on any net profit whereas they only pay tax on nonexempt function income (interest,etc). That could account for why many assn's file the 1120H. It's best to consult with a CPA to determine which form is best suited for your assn.