Rail pass valid on Keisei line?

Is the Japan Rail Pass valid on the Keisei lines between Narita Airport and Nippori. If not, how do I get from the airport to Nippori station without using Keisei trains?

No the JR Pass is valid on JR trains. The Keisei train is of course Keisei Railways.

If you have a JR Pass and wanted to get to Nippori Station from Narita Airport.

Take the Narita Express to Tokyo Station, then change to the Yamanote Line or Keihin Tohoku Lines to Nippori Station.

Is the Japan Rail Pass valid on the Keisei lines between Narita Airport and Nippori. If not, how do I get from the airport to Nippori station without using Keisei trains?

I suggest you not to waste one day portion of your JR pass merely for transport from NRT to central Tokyo.

The Keisei limited express costs only 1,000 yen, and a 'SUica and NEX' package is a good deal for 3,500yen
http://www.jreast.co.jp/e/suica-nex/index.html

Thanks for the info. In that case I think a rail pass will not save us any money for the first 6 days (in Tokyo). I've just been checking prices and the local trains are actually quite cheap (i.e. Nippori - Shinjuku only 190 yen), so I think I'll get a 2 week pass instead of a 3 week pass.

Iread you can use Suica on Keisei limited express line, but not on Keisei skyliner. Is this correct?
Can you buy Suica at Narita airport? (I don't want "Suica & N'EX", because I want to use the Keisei line.)

I would also like confirmation of this.

Can you purchase a prepaid Suica card from the JR office (midori no madoguchi) at Narita Airport, and then straight away use that on the other company's train (the cheaper Keisei line)?

And because the JR midori no madoguchi accepts credit cards, does that mean you can (indirectly) pay for Keisei line (as well as the other Suica-accepting services) by credit card?

Iread you can use Suica on Keisei limited express line, but not on Keisei skyliner. Is this correct?
Can you buy Suica at Narita airport? (I don't want "Suica & N'EX", because I want to use the Keisei line.)

You can use the Suica card on both.

Ok what the Suica card allows you to do is enter and exit stations.

The suica card covers the base fare on the Keisei Limited Express and the Skyliner and any train in the area.

But the skyliner requires an additional seat reservation fee.

So YES you can use the Suica to ride the Skyliner (again all it is is just to enter and exit the stations), you just need to pay for an additional seat reservation to ride the skyliner. The newer seat reservation machines accept Suica, otherwise pay cash for the additional seat reservation at the seat reservation machine located on the platform.

You can get a seat reservation at the counter but if you're Japanese isn't too good, or their english isn't too great they might sell you a full ticket with seat reservation.

Zavo, Keisei railways and most other railways except JR sell their own card called PASMO, aside from the name its almost exactly like Suica, and you can use it where Suica is accepted and vice-versa.

So again, you can use Suica/Pasmo to ride the Skyliner if you wanted to. You just need to purchase an additional seat reservation.
So just use your card to enter through the gates, purchase the seat reservation on the platform at the machine, ride the train, use the suica/pasmo card to exit the station.
Easy.

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Anon, if they sold you a plain Suica card with a credit card (not sure if they do for suica cards or not)
Then you can use the card for any services that is compatible with Suica, eg the PASMO system that Keisei Railway uses.
There's nothing limiting you from using the Suica card on another railway system that is compatible with it.