# Bank and customer relationship: key duties

> **Key takeaway:** Contract + mandate. Quincecare: don't pay if fraud red flags on agent instructions (limits in Philipp for customer-authorised APP fraud). PSRs on unauthorised payments. Tournier confidentiality. Check current APP reimbursement rules.

- **Jurisdiction:** England & Wales
- **Practice area:** Commercial
- **Last reviewed:** 2026-08-04
- **Interactive page:** https://kttclegal.info/library/notes/Commercial/banking-and-customer-duties
- **Keywords:** bank customer, Quincecare, Singularis, Philipp, APP fraud, Payment Services Regulations, Tournier, mandate

## What is this about?

The bank–customer relationship is primarily contractual, with implied terms and tortious duties in limited situations. Payment mandates, Quincecare duties, and statutory payment services rules structure modern disputes about unauthorised or fraudulent payments.

## What is the core rule?

A bank must generally honour its customer's mandate when the account is in credit or within agreed facilities, and must exercise reasonable care in interpreting and executing payment instructions. The Quincecare duty requires a bank not to execute a payment instruction if on inquiry it has reasonable grounds for believing the instruction is an attempt to defraud the customer (Singularis; Philipp themes on APP fraud limits). Payment Services Regulations allocate liability for unauthorised payment transactions. Confidentiality (Tournier) binds banks subject to compulsion of law, public duty, bank's interests, and customer consent.

## What are the elements or test?

1. Contractual mandate terms and account conditions?
2. Was the payment authorised under the mandate?
3. Quincecare red flags / duty to inquire engaged?
4. PSRs unauthorised payment allocation?
5. Confidentiality exception applicable?

## Which authorities matter?

- **Tournier v National Provincial and Union Bank of England [1924] 1 KB 461** — Classic bank confidentiality duty and exceptions.
- **Barclays Bank plc v Quincecare Ltd [1992] 4 All ER 363; Singularis Holdings Ltd v Daiwa Capital Markets Europe Ltd [2019] UKSC 50** — Duty not to execute payments amid fraud red flags; Supreme Court on attribution/defence issues.
- **Philipp v Barclays Bank UK plc [2023] UKSC 25, [2023] 3 WLR 284** — Supreme Court on limits of Quincecare where the customer itself authorises the payment (APP fraud context).
- **Payment Services Regulations 2017 (as amended)** — Statutory framework for payment service liability and authorisation.

## How does this apply in practice?

APP fraud reimbursement schemes and PSR policy evolve — check current mandatory reimbursement rules. Corporate vs consumer accounts differ. Pair with data protection and FS regulation notes.

## What are common pitfalls?

- Over-extending Quincecare after Philipp without analysing who authorised
- Ignoring mandate terms and confirmation of payee processes
- Confidentiality breaches in reference requests
- Missing PSR time limits for notifying unauthorised transactions

## When would a practitioner use this?

Payment fraud claims against banks; advising on internal payment controls.

## Quick reference

Contract + mandate. Quincecare: don't pay if fraud red flags on agent instructions (limits in Philipp for customer-authorised APP fraud). PSRs on unauthorised payments. Tournier confidentiality. Check current APP reimbursement rules.

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*Reference material from [KTTC Legal](https://kttclegal.info/), not legal advice. Work product supports instructing solicitors and barristers under their supervision. England & Wales.*