Martell is located west of Jackson and east of Ione, by which it is connected by the Amador Central Railroad. Martell is where several major retail and restaurant outlets for Amador County are located.
The Census reported that 217 people (77.0% of the population) lived in households, 65 (23.0%) lived in non-institutionalized group quarters, and 0 (0%) were institutionalized.
There were 97 households, out of which 23 (23.7%) had children under the age of 18 living in them, 32 (33.0%) were opposite-sex married couples living together, 17 (17.5%) had a female householder with no husband present, 7 (7.2%) had a male householder with no wife present. There were 7 (7.2%) unmarried opposite-sex partnerships, and 0 (0%) same-sex married couples or partnerships. 32 households (33.0%) were made up of individuals, and 6 (6.2%) had someone living alone who was 65 years of age or older. The average household size was 2.24. There were 56 families (57.7% of all households); the average family size was 2.80.
The population was spread out, with 43 people (15.2%) under the age of 18, 43 people (15.2%) aged 18 to 24, 77 people (27.3%) aged 25 to 44, 93 people (33.0%) aged 45 to 64, and 26 people (9.2%) who were 65 years of age or older. The median age was 41.7 years. For every 100 females, there were 89.3 males. For every 100 females age 18 and over, there were 91.2 males.
There were 114 housing units at an average density of 48.8 per square mile (18.8/km2), of which 97 were occupied, of which 53 (54.6%) were owner-occupied, and 44 (45.4%) were occupied by renters. The homeowner vacancy rate was 0%; the rental vacancy rate was 16.7%. 124 people (44.0% of the population) lived in owner-occupied housing units and 93 people (33.0%) lived in rental housing units.
^ abDurham, David L. (1998). California's Geographic Names: A Gazetteer of Historic and Modern Names of the State. Clovis, Calif.: Word Dancer Press. p. 519. ISBN1-884995-14-4.