Because you were focusing so much on verbal, I thought you were interested in businesses with revenue > $1 million. Sorry.
For those with revenue of $1 million or less the rules differ and are more like consumer:
(a)(3) Notification to business credit applicants. For business credit, a creditor shall comply with the notification requirements of this section in the following manner:
(i) With regard to a business that had gross revenues of $1 million or less in its preceding fiscal year (other than an extension of trade credit, credit incident to a factoring agreement, or other similar types of business credit), a creditor shall comply with paragraphs (a)(1) and (2) of this section, except that:
(A) The statement of the action taken may be given orally or in writing, when adverse action is taken; CAN BE VERBAL
(B) Disclosure of an applicant's right to a statement of reasons may be given at the time of application, instead of when adverse action is taken, provided the disclosure contains the information required by paragraph (a)(2)(ii) of this section and the ECOA notice specified in paragraph (b)(1) of this section; MUST BE WRITTEN UNLESS APPLICATION IS ENTIRELY BY TELEPHONE, BUT CAN BE AT TIME OF APPLICATION, SUCH AS ON AN APPLICATION FORM, OR ON A SEPARATE FORM HANDED OUT.
(C) For an application made entirely by telephone, a creditor satisfies the requirements of paragraph (a)(3)(i) of this section by an oral statement of the action taken and of the applicant's right to a statement of reasons for adverse action.
(a)(1) and (2) referenced above state the following and you must comply verbally or in writing (so you have 30 days to comply on the small businesses, but that can be verbal or written, unlike consumer which must be written):
(a) Notification of action taken, ECOA notice, and statement of specific reasons. (1) When notification is required. A creditor shall notify an applicant of action taken within:
(i) 30 days after receiving a completed application concerning the creditor's approval of, counteroffer to, or adverse action on the application;
(ii) 30 days after taking adverse action on an incomplete application, unless notice is provided in accordance with paragraph (c) of this section;