The United Forum of Bank Unions (UFBU), which brings together seven employee and officer unions, has called the action. Cash transactions and cheque processing could face delays as staff participation affects branch services.

The unions say their demand for a shorter working week remains unresolved. AIBOC’s Rupam Roy and NCBE’s L Chandrasekhar have sought parity with other financial institutions. They point to five-day schedules already followed by the RBI, LIC and most government offices.

Retirement benefits are another key issue. The demands include pension revisions, a common Dearness Allowance arrangement for pensioners and an option for employees covered by NPS to switch to OPS. Discussions involving the Chief Labour Commissioner have not produced a firm government commitment.

The weekend after the strike could extend branch closures to three days. In states observing the Ganesh Chaturthi holiday on September 14, the interruption could last four days. SBI has alerted customers to possible disruption, saying staffing shortages could affect branches despite contingency arrangements.

UFBU has also warned of a further three-day stoppage beginning September 28, overlapping with half-yearly account closing. Customers should finish urgent branch-dependent work ahead of Friday. ATMs, mobile banking and internet banking are expected to remain available, but services needing an officer’s approval or an in-person visit may be delayed.