N.H. Rev. Stat. § 282-A:61
The commissioner shall render his or her determination within a reasonable period after all the facts or arguments are made available to him or her. The determination of the commissioner shall be sent by certified mail, return receipt requested, or first class mail, whichever the commissioner determines to be the most appropriate, to each interested party at the last address of each according to the records of the department of employment security. The appeal tribunal shall, upon direction to reopen, proceed in the same manner as though an appeal in said case were being taken from a determination of a certifying officer; provided, however, that the further hearing shall be limited to the introduction of evidence or argument relative to and concerning the factors which constitute the basis or ground for the reopening unless the commissioner orders a de novo hearing.
RSA 282-A:61
1937, 178:1. 1939, 138:13. 1941, 103:21-23. RL 218:5. 1945, 138:11, 12. 1947, 59:14, 15. 1949, 185:7-10; 290:2. 1951, 36:2; 140:8; 142:7, 8. 1953, 209:4. RSA 282:5(2)(E). 1955, 71:1; 141:10, 11. 1957, 118:6. 1961, 88:10-16. 1965, 208:6, 7; 373:2. 1969, 460:8-10. 1971, 156:23; 539:16-19. 1973, 119:1; 589:5, 6. 1981, 408:3; 576:7. 1987, 409:6, eff. July 1, 1987. 2013, 39:2, eff. Aug. 3, 2013.