A party served in Washington has 20 days to answer. A party served outside of Washington has 60 days. Your question leaves out some details but I infer that the company was served personally inside the state (that is, given to a managing agent or registered agent, not by publication in a newspaper) and the case is in a Washington court. If so, you have 20 days. The out-of-state location of the company's head office does not enlarge the time for answering. You can get more time to put the case together, but the answer deadline for a summons is a short fuse which needs immediate attention.
This answer is intended as a courtesy only, and does not constitute an attorney-client relationship between the attorney and the questioner.