1. Why Working Papers Are Mandatory?

A. RBI - Master Direction on Interest Rates:
Bank must be able to demonstrate that interest charged is as per disclosed policy, sanction terms and RBI directives on penal charges. RBI Circular on Fair Lending - Penal Charges to be disclosed separately, cannot be compounded.

B. Accounting Standard - SA 230 - Audit Documentation:

Auditor must document matters which are important in providing evidence to support audit opinion, and working papers must include auditor's reasoning on all significant matters which require auditor's judgment.

If bank itself has no working papers, auditor cannot obtain Sufficient Appropriate Audit Evidence (SA 500). Result - Qualified Opinion or MOC.

C. ICAI Disciplinary Code:
Failure to maintain and produce working papers is professional misconduct under Clause 5,6,7,8 of Part I of Second Schedule of CA Act.

Recent Order 5 Feb 2026:

A statutory auditor was held guilty under Clauses (5), (6), (7) and (8) of Part I of Second Schedule and given reprimand, Rs.5 lakh fine and removal for 1 year. He could not produce his working papers, saying they "remained with the firm". Funds were lent interest-free to group companies and related party disclosures inadequate. Committee highlighted duties of auditor to maintain working papers and documents and noted that in spite of being repeatedly directed, respondent did not produce papers and took plea that since 2003 he surrendered certificate, therefore not keeping past record.

Same applies to Bank officer - if you cannot produce working, it is deemed you never computed it correctly.

2. What Constitutes Working Papers for Interest?

For every account, bank must preserve:

1. Sanction Working: ROI - E.g., EBLR 8.55% + Spread 2.5% + Risk Premium 0.5% = 11.55%
2. Amendment Letters: If ROI revised, date of implementation
3. CBS Parameter Sheet: Interest Code Master - Print screen
4. Day-wise Product / Balance Sheet: For CC - Daily balance x rate
5. Manual Computation Sheet: For NPA - Interest at simple rate, not compounding after NPA date as per Supreme Court judgment
6. Penal Interest Sheet: Separate disclosure
7. Certificate of Compounding: Quarterly rests as per agreement, not monthly

Failure to provide = LFAR point - Revenue Leakage / Excess Charging.

3. Case Laws - Interest Computation Disputes

A. Civil Suit for Excess Interest Charging:

Case: P Mallikarjuna Chetty vs City Union Bank - Bengaluru LXIII Addl. City Civil and Sessions Judge - Judgment 9 Oct - Judge I P Naik

Businessman filed suit alleging City Union Bank wrongly calculated interest and collected Rs.16.42 lakh excess while recovering overdraft dues. He questioned interest rates of 14.25%, 15.25% and 16% applied to OD facilities and disputed method of compounding. Bank failed to provide adequate documentation supporting interest calculation. Court ordered bank to refund Rs.16.42 lakh with Rs.3 lakh compensation.

Principle: If bank cannot produce working papers for rate changes and compounding method, Court will accept borrower's version and treat it as deficiency of service.

B. DRT - Interest Not Substantiated:

Case: ICICI Bank Ltd vs Jyoti Malik - DRT Lucknow 21 Nov 2022
Tribunal relied on Central Bank of India vs Ravindra AIR 2001 SC 3095 - Landmark on interest.

Tribunal identified discrepancies in bank's calculation of interest and penalties. It observed interest rate of 9.52% was not adequately substantiated by loan agreements or pre-disbursement working. Bank claimed compounded interest and penal interest without working. DRT disallowed penal interest and reduced future interest.

Case: Bank of Rajasthan Ltd vs GSL Products - DRAT Mumbai 27 Jan 2004
DRT Jaipur decreed Rs.4,08,78,198.59 with interest at 17.5% p.a. DRAT held learned Presiding Officer did not grant penal interest and did not award compounded interest because bank failed to produce working papers for penal interest and compounding rests.

Case: State Bank of India vs Mining Engineering Corporation - DRAT Madras 27 June 2006
Bank claimed interest @16.5% simple but DRT awarded 16.5% compounded quarterly. On appeal, DRAT held Bank is entitled to claim interest only as agreed and as per working produced. Since bank filed suit claiming simple but claimed compounding without working, compounding disallowed.

C. Supreme Court on Interest - Central Bank of India vs Ravindra - AIR 2001 SC 3095 - Bible for Interest
Supreme Court held:

1. Interest after filing suit (pendente lite) is discretion of Court under Sec 34 CPC, not contractual rate.
2. Compounding of interest on NPA is not allowed - banks cannot compound interest on NPAs quarterly to increase dues.
3. Capitalization of interest (interest on interest) after account becomes NPA is illegal.
4. Bank must prove contractual rate with working - if no working, Court will reduce to reasonable rate (PLR / Repo based).

D. DRAT Kolkata - Rate of Interest in Settlement - Appeal No.219/2018
DRT allowed IA and directed respondents to pay balance OTS amount of Rs.53 lakhs along with interest at 4% p.a. Bank challenged saying contractual rate was 14% and 4% was erroneous. DRAT held DRT has power to fix reasonable interest below contractual rate under Section 34 CPC, but must be based on working and reasonableness. If bank does not produce working of loss due to delay, Court can fix lower rate.

E. ICAI - Auditor Liability for Not Obtaining Interest Working:

Case: Council of ICAI vs Somnath Basu - AIR 2007 Calcutta 29 & ABCAUS 2572 (2018) (10) AA
CA held guilty of misconduct by not obtaining bank confirmation letter and interest computation working by exercising due diligence when fake statement was only a printed paper with no signatures or seal. Auditor accepted interest certificate without working papers.

4. Audit & Legal Impact

If working papers not provided:

1. Revenue Audit: Entire interest to be recalculated, difference = Revenue Leakage (if undercharged) or Excess Recovery (if overcharged - refund with interest @18%)
2. Statutory Audit: MOC - "Interest on CC accounts amounting to Rs.XX Crore could not be verified for want of working papers"
3. DRT Case Fails: In Bank of India vs Paras Talkies 2025 LiveLaw (Raj) 330, High Court upheld DRAT reducing interest rate from contractual to reasonable because bank failed to produce working of penal interest.
4. Consumer Case: Deficiency of service under Consumer Protection Act - Bank ordered to refund excess interest with compensation.
5. RBI Inspection: Under Risk Based Supervision, non-maintenance of interest computation sheets is categorized as - Non-compliance with Fair Practices Code - penalty under Sec 47A BR Act.

5. How to Rectify & Checklist

For Audit File, demand:

• CBS Interest Parameter Report (IT-004)
• Sanction letter ROI clause + EBLR change circulars
• Day-wise interest run for test check - Recompute: Interest = Outstanding * ROI * Days / 365 or 360 as per product
• For NPA: Ensure no compounding after NPA date - Verify with Central Bank vs Ravindra
• Penal interest working - separate from normal
• Approval for interest waiver / concession

If bank uses manual interest (Staff loans, NPA recalled accounts), demand Excel working signed by Officer and Branch Manager.

LFAR Draft Language:

"In respect of XX borrowal accounts (Total outstanding Rs.YY Cr), interest working papers / calculation sheets / rate revision letters were not made available for verification. In absence of same, correctness of interest charged to the tune of Rs.ZZ Lakhs could not be verified. We could not satisfy ourselves regarding compliance with RBI guidelines on interest rates and Supreme Court ruling in Central Bank of India vs Ravindra. Branch to preserve interest computation trail as per SA 230 and produce for audit."