It's Nepal's statutory contributory social-security scheme, brought in under the Social Security Act 2074 and managed by the Social Security Fund (ssf.gov.np). Enrolment is compulsory for employees in the organised sector and the fund provides four categories of protection — health, accident, life cover for dependants and a retirement pension.
In total, 31% of basic salary — split as 11% from the employee and 20% from the employer. The employer's share is further distributed across Medical and Health (1%), Accident and Disability (1.4%), Dependent Family (0.27%) and Old Age Pension (17.33%).
Off basic salary only. Allowances — house rent, dearness, medical, travel, and any other add-ons — do not feed into the SSF base. Both the 11% employee and 20% employer contributions apply to the same basic figure.
Four benefits: (1) medical, health & maternity — hospital and maternity care; (2) accident & disability — payouts for workplace injuries; (3) dependent family protection — life cover for nominees; (4) old age pension — monthly pension after retirement. Full eligibility detail is on ssf.gov.np.
EPF was a 10% + 10% (20%) retirement-savings pot. SSF replaced it under Act 2074 and raised the total to 11% + 20% (31%), but in exchange the scheme now pays for medical care, workplace accidents, life cover and a proper pension. EPF simply wasn't designed to do any of that.