From the US PTO site,  explaining when to use TEAS or TEAS PLUS when filing trademark applications electronically:

 

Which type of form do you wish to use? Select from one of the two versions, below, and then click on the CONTINUE button at the bottom of the page.
TEAS Plus Form
This form has a lower filing fee of $275 per class of goods and/or services, but has stricter requirements, than the TEAS form, below. Select this option ONLY if you agree to:

  • file a “complete” application that satisfies all requirements set forth in Rule 2.22(a), not only the regular “minimum requirements” for obtaining a filing date. Almost all fields in this form are mandatory;
  • select the listing of goods and/or services for this application directly from the USPTO’s Acceptable Identification of Goods and Services Manual. While certain listings will allow for “customization,” total “free-text” entries for identifications CANNOT be made;
  • attach all required image files, where applicable, in the .jpg format (for specimens, foreign registration certificates, consents, evidence) (except for sounds marks, for which a .wav or MP3 file can be submitted separately);
  • pay the fees for ALL classes at the time of filing;
  • file certain later communications regarding the application, such as a response to an Office action, through TEAS. See Rule 2.23(a)(1) for the listing of forms that must be filed through TEAS; and
  • receive communications concerning the application by electronic mail (e-mail) during the pendency of the application.

NOTE: If you use the TEAS Plus version of the form, you must pay an additional fee of $50 per class if, at any time during the examination of the application, the Office determines that (1) the application did not meet the filing requirements for a TEAS Plus application as of the filing date, as set forth in Rule 2.22(a); (2) the applicant files a paper form after the initial application, but a TEAS form existed for that purpose, e.g., a response to an Office action; and/or (3) the applicant refuses to receive correspondence from the Office by electronic mail (e-mail) during the pendency of the application.

You must select this option, having a filing fee of $325 per class of goods and/or services, if you:

  • cannot file a “complete” application at this time, satisfying all requirements as set forth in Rule 2.22(a), but instead can meet only the “minimum requirements” for obtaining a filing date. Only certain fields on this version of the form are mandatory;
  • wish to make a “free-text” entry for the listing of goods and/or services for this application, rather than selecting the listing directly from the USPTO’s Acceptable Identification of Goods and Services Manual (apart from any permissible “customization” within certain listings);
  • are unable either to create or successfully attach in the designated portion(s) of the form a proper .jpg image file, if applicable for the application (for specimens, foreign registration certificates, consents, evidence);
  • wish to pay for only one class at the time of filing, although the application as filed will consist of multiple classes;
  • plan later to file certain communications regarding the application, such as a response to an Office action, in paper rather than through TEAS. See Rule 2.23(a)(1); and
  • do not agree to receive communications concerning the application by electronic mail (e-mail) during the pendency of the application.