A research was conducted in Jalpadevi, Gajra and Payal wards of Achham district to assess the determinants and socio-economic impact of labour out-migration among farming households. All together 180 households comprising 90 migrating and 90 non-migrating households were sampled and interviewed. The average land holding size, irrigated land holding size, livestock holding were found higher in non-migrating households. Migrating households experienced decline in livestock holding after migration. Family size of the household, migration status of the he-parent of household head positively and significantly affected the decision of household for migration whereas the variables education status of household head, association with farmer's group and distance from the market center were found to have significant negative role in the household migration decision. The quantity of production as well as productivity of rice and wheat were found to be higher for the non-migrating households as compared to that of migrating households. The annual agricultural income was significantly lower for migrating household than the non-migrating household and agricultural income reduced in the migrant household after migration. While majority of the migrants perceived improvement in education and health status of their household members, childcare and agricultural production suffered as a result of out-migration. Share of remittance used by the migrant households for agricultural purpose was found very low and larger proportion was spent on food clothing and luxurious items.