Do I have to file an s-corp tax return?

When did you dissolve it- this year or last year?

If this year, it's best to file a return listing $0 throughout, but not everyone bothers to do that.

If last year, I don't know.

I believe you do have to file a tax return. It's your way of proving that you don't owe any taxes to the government. And as Tim pointed out, check the final return box. There's also an initial return box, you may want to check that one as well.

You said that you didn't have any revenue, but did you have any expenses? Since you are filing the return you might as well deduct your business expenses to offset any other income you made during the year. Even if you didn't have any business expenses, at the very least you can deduct the fees you had to pay the state of CA to register your business.

Any corporation MUST file a yearly tax return as long as it exists. When you dissolve the corporation, you must file a "final" return, which should cover all your liabilities and expenses, including those incurred when dissolving the entity.

If the business has never actually existed, I would suggest filing a zero return (no income, no expenses), unless you can substantiate all the business-related expenses and prove the intention to start a business and explain why it didn't work out properly. Generally speaking, IRS might re-characterize these expenses as "hobby" expenses which are not deductible. Forming a corporation to deduct expenses which are otherwise non-deductible is a known trick, so it will likely to trigger an audit.

Make sure to consult with a tax professional (EA/CPA). This answer was not intended or written to be used, and it cannot be used by any taxpayer, for the purpose of avoiding penalties that may be imposed on the taxpayer (circ. 230, as I am a tax practitioner).