Subject line says it all.

Here's my situation:
-I am the sole owner of a Delaware S-CORP. 
-I run the business out of my home in Delaware
-I have no employees.
-Today (and for the last 5 years), I happen to live in Delaware. 
-When I started the business, I decided to do it with an firm which
acts as my "Registered Agent." I am in "good standing" with my
registered agent.
-Today, my tax situation and business life is pretty simple: 
    -The business "pays me" a salary every other week
    -The business pays quarterly Delaware state tax (and, of course
Fed tax for my business.)
    -I (personally) pay quarterly Delaware state tax (and, of course Fed tax)

Soon, I am likely moving to Pennsylvania, specifically, Philadelphia.

If I understand correctly, PA (of course) has STATE
tax, and Philly has its own CITY WAGE tax.

So, here's the question:

When I sell my DE house and move to PA (Philly) -- what taxes do I end up paying?

Remember -- my company is incorporated as a Delaware S-CORP,
and my house, today, is in DE. But my "base of operations" 
is moving to Philly.

So... I'm confused (and getting different advice from different
"professionals" in both DE and PA.) PA professionals are saying I'm
going to have to pay PA state and Philly city wage tax. DE
professionals are saying I'm A-OK just "doing what I've always done."

How to give me your answer:
Please let me know (with references to tax codes or whatever)
precisely what will be changing for me and why. Honestly, "tighter"
answers are better for me than long winded ones. I'm a successful
computer geek with a small business -- not a tax geek. So "dumbing it
down" for me is somewhat encouraged. Though, whatever answer you
provide I'll want to be able to reference intelligently with both my
DE and PA tax people as reference, so, please keep that in mind too.

Thanks.

Contact the DE state dept of revenue & tell them you are moving
yourself & your business base of operations from DE to PA & ask what
forms you need to file to notify them that your business will no
longer be subject to DE tax.

You'll need to pay DE taxes as long as you are resident in DE. The
fact that your company is incorporated in DE is largely irrelevant --
huge numbers of corps are registered as "DE corps" & never do business
in DE or pay DE taxes. Be sure to document how much of your wages were
earned in DE & how much in PA. At tax time, you'll issue yourself 2
W-2's showing each state's wages & withholding. You will file 2
"part-year resident" returns.

The key factor in determining where you pay taxes is where you are
performing the services. Once you move to PA, you'll have to pay PA
taxes, but no longer pay DE taxes. PA has a local earned income tax in
many areas. Your PA local taxes will be determined by where you
reside. If you live outside the city limits of Philly, you'll pay the
county wage taxes.

I suggest you find a good payroll company for the first year, just to
make sure everything's set up correctly.

Here are some links to explain the various local taxes in PA:
http://cax.aers.psu.edu/taxreform/localtax.htm
http://pittsburgh.about.com/od/taxes/a/pa_taxes.htm
http://www.phila.gov/revenue/

Hi Jeremy,

State and local taxes are paid in the place where your business takes
place.  Your "office" will be in Pennsylvania once you move.  You will
need to register with the PA state government for your business
withholding tax identification number.  You can do this at
(www.paopenforbusiness.state.pa.us)Filling out the PA100 form will
give you a withholding ID number within days.  Since you have no
employees you do not need an unemployment ID.  As for your local ID,
you can contact berkheimer (the local tax authority for Philadelphia)
at 610-588-0965.  The Philadelphia Business Tax is only if you live or
work in Philadelphia.  The application for this tax ID can be found at
(http://www.phila.gov/li/faq/83-T-5.pdf#search=%22Philadelphia%20business%20tax%20application%22)
or if that link doesn't work (www.phila.gov/li).

I hope this helped.  I actually work in the Philadelphia area for
Automatic Data Processing.  I don't have any official documentation
but I deal with businesses in your situation at least once a month.

The general rule of thumb is: you pay federal tax where your company
is incorporated but you pay state tax where you business resides.

Let me know if you have any questions!
Megan