Halt Unchecked Member Benefits with Lobbying Elimination Act or the HUMBLE Act This bill bans lobbying by former Members of Congress, eliminates certain benefits and services for former Members of the House of Representatives, limits the use of congressional funds for official travel, and restricts investment and other activities of House Members. Specifically, former Senators, former House Members, or former elected officers of the House or Senate may not communicate with or appear before any Member, officer, or employee of a congressional legislative office seeking action on behalf of any other person, except the United States. (Currently, former Senators are subject to a two-year ban on lobbying, while former House Members and former elected officers are subject to a one-year ban.) Additionally, former House Members may not access certain benefits and services (e.g., access to the House Chamber, the Members' Dining Room, or parking spaces) unless those benefits and services are publicly available. Further, when purchasing airfare, Members of Congress (and legislative branch employees) may only use official travel funds to purchase coach-class tickets unless applicable regulations would authorize the purchase of a higher class of ticket for a federal employee. House Members may not (1) own common stock in individual corporations, or (2) serve on boards of for-profit entities. The bill also eliminates one day of pay for each House Member for any day of a Congress during which no Speaker has been elected.