Zip to District Tables Q & A

Q:  What's the difference between the Postal Service-based congressional zip to district table and the Capitol version?

A:  It's in the way the tables are put together. The Postal Service table is based entirely on congressional district assignments to zip codes that are done by USPS state and regional offices. The Capitol version is put together using a combination of Census data and geocoding (where longitude and latitudes are assigned to each zip and accompanying zip plus4), a long and tedious process.

Q:  Why shouldn't I just go to the Postal Service and do my own table?

A:   It would cost you you nearly three times what we charge for the table and then you would have to do a considerable amount of programming to pull the table out of the raw Postal Service data. And then you'd be dealing with 8 gigs of data and more programming to get it down to a manageable size (when our programming is done our table in the Access format is about 35 megs, the text table is about 15 megs).

Q:  How accurate is the Postal Service version of the congressional zip to district table.

A:  It's pretty accurate. It runs with about a 2 to 3 percent margin of error, where you might know that you live in congressional district 2, the Postal Service data might show you in district 3.

Q:  Does the Postal Service ever correct these errors?

A:  Yes. We started testing the Postal congressional zip-to-district table in January 2005 and it was amazing how good the Postal Service had gotten with their data. The Postal Service had really improved over their past performance, they're doing an impressive job. If you get the Postal Service table and find something you know is incorrect send it to us and we'll pass it on to the Postal Service.

Q:  How often are the Postal Service-based and Capitol version zip to district tables updated ?

A:  Quarterly.

Q:  What format or formats do they come in?

A:  Access 2000, a text file, or dBase IV.

Q:  So what do we do if we want to go ahead and subscribe to your Postal Service zip to district database ?

A:  Send an e-mail stating that fact to Michael Waters (be sure to include your name, organization's name, mailing address, and other contact information). A license agreement and an invoice will be sent to via return e-mail. Sign and fax the license agreement back to Congress Merge (you'll be given the fax number when you're sent the license agreement) and we go from there.  It's possible to get your data the same day.

Q:  What's this license agreement?

A:  Subscribers to our Postal zip-to-district data (and our other data products as well) agree to use it for themselves in an internal database or on a web site and not to distribute it to third parties. Here is some of the wording from the license agreement:

(Name of Client) agrees to use the data only for itself (either in an internal database or for a web site) and that additional uses can be granted only after the signature of another license agreement and the payment to Congress Merge of the appropriate fees for the data at the time of further agreements. . . .

(Name of Client) will not otherwise distribute the "Data" to any other individual or organization.

Q:  Does this licensing agreement mean I can only install the database on one machine?

A:  No. Install it on as many machines as you like as long as you don't give it to a third party, you're fine. In fact, you can install it on a network if you'd like -- all at no extra charge.

Q:  Does it come with a listing of members of Congress and their contact information?

A:  Yes. We give each subscriber a list of all members of Congress and their Washington, DC, contact information  This information is provided in a text file that is updated weekly while Congress is in session.  If you want committee/subcommittee assignments, district office information, and key staffers please see the question below.

Q:  Can we also subscribe to your congressional database.

A:  Yes. If you get the either the Postal Service-based or the Capitol versions of our congressional zip-to- district tables and and also purchase the congressional information database we'll deduct $100 off the total price.  Our congressional information database is updated frequently, sometimes daily, to reflect changes on the Hill, be they e-mail changes, district office changes, or committee and subcommittee assignments. Please use this link for more information on our congressional information database.

Q:  Would the same licensing agreement apply to the congressional information database?

A:  In essence, yes. The only difference is that the congressional information database is cited in the agreement. And, as with the Postal Service-based zip-to-district table, you can load the congressional information database on a network or on as many individual machines as you'd long as you don't give it to a third party -- all at no extra charge.

Q:  Should I expect my annual fee to go up in the years ahead?

A:  No. As long as you are a Congress Merge subscriber your price will stay the same.

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