At IU:

Phi Mu and Alpha Tau Omega are Delta Alpha chapters
Delta Tau Delta and ADPi are Beta Alpha chapters
Pi Beta Phi and Phi Kappa Psi are Indiana Beta chapters
Kappa Alpha Theta and Sigma Pi are Beta chapters.

At Iowa State both Kappa Alpha Theta and Delta Tau Delta are Gamma Pi chapters.

In Alpha Sigma Phi, it's by Greek alphabetical order by date of installation, omitting Omega and any double-letter combination ending in Omega.

Hmm, several people have mentioned the omega thing. Am I a retard or is there something bad luck about Omega? Other than its the last letter of the alphabet and people are supersticious about it being last?

Tri Sigma doesn't use Omega in it's chapter designations because the Omega chapter is the chapter reserved for those sisters who pass away. Several other groups do the same. It's just tradition.

I believe that both Chi Omega and Delta Zeta's chapter designations at Louisville are "Beta Gamma".

That is my chapter. And pull at my heartstrings since my chapter was closed in May.

I always say "Delta Gamma, University of Arizona" just because it's the name of another sorority (that ironically is directly across the street from the ADPi house at U of A)

End of my little mini hijack

Chapter Designation
 

By coincidence, the local chapter that became the Delta Lambda chapter of Zeta Tau Alpha was Delta Lambda Sigma. It was a 20+ year old local chapter at Georgia State University before being chartered in 1961. Our chapters are named in Greek alpha order, too, although I do know of one exception.

I had the priviledge of meeting some of the Delta Lambda Sigma alumnae last year. For reasons I don't quite understand, they chose not to be initiated upon installation, as is our custom. To this day they still wear their Delta Lambda Sigma badges when they get together. It was really cool.

In Alpha Sigma Phi, Omega, along with being the 24th and last letter of the Greek alphabet, it traditionally signifies 'the end'. As such, Omega Chapter is the chapter reserved for initiates who have passed away. We traditionally list initiates who have entered Omega Chapter by listing the initiating chapter year and the year the brother passed away as the year he entered Omega. Example: Louis Manigault (our founder), Alpha 1845, Omega 1899.

Both Phi Mu and Alpha Gamma Delta are Mu chapters at Brenau Univ. in Gainesville, Ga.

It's not bad luck. My org and several others have an Omega Chapter. We use a different terminology for our deceased Sorors.