SWIFT / Learning brief
IBAN Plus, SSI, and routing directories
Your notes
In simple terms / 01
What this means in plain language
IBAN Plus derives the correct BIC from an account number, the SSI Directory records where and how to settle, the SEPA routing directory shows reachability, and RMA Plus governs granular messaging authorisations.
A cross-border payment needs three kinds of answer: which institution owns the account, where and how that institution wants to settle, and whether it can be reached at all. Four SWIFTRef resources cover these. IBAN Plus takes an IBAN (International Bank Account Number) and derives the correct BIC (Business Identifier Code) for it, so a payment captured with only an account number can still be routed to the right institution. The SSI (Standing Settlement Instructions) Directory records the standing agreements for where and how two parties settle a given currency, so operations do not have to chase those details each time. The SEPA (Single Euro Payments Area) routing directory lists which institutions are reachable for euro scheme payments and by which route. RMA Plus manages Relationship Management Application authorisations, the granular permissions that say which counterparties may exchange which message types. Each directory answers a distinct routing or permission question.
Complete lesson / 02
Understand the full idea, step by step
Read out a long European account number and you have said a great deal — a country, a bank's domestic account, a built-in check — but you have not said which institution a cross-border system should send the money to. That last translation is a job in itself, and it is the first of four separate questions a payment quietly has to answer before it moves.
IBAN (International Bank Account Number) — a standardised account number that embeds a country and a domestic account
An IBAN identifies a specific account and carries a country code, a check figure, and the domestic account portion. It says a great deal about the account — but on its own it does not tell a routing system which BIC to send the payment to. That is the gap IBAN Plus closes.
IBAN Plus: from account number to institution
IBAN Plus takes an IBAN and derives the correct BIC for the institution that holds the account, so a payment can be routed even when the sender supplied no institution code. This matters because a guessed or hand-keyed BIC is a common source of misrouting and repair — one of the most avoidable ways a payment goes wrong. Deriving it from a trusted directory removes the guesswork and lets validation happen automatically at capture. Like all reference data, it describes the structure connecting accounts to institutions; it does not confirm that a particular account is open, so it complements rather than replaces any account-level verification.
SSI (Standing Settlement Instructions) — agreed-in-advance details of where and how to settle a currency
The SSI Directory records, for a given party and currency, the account and route to be used for settlement. Standing means the instruction is held on file and agreed in advance, so operations teams do not have to request settlement details for every payment. Without it, those details are exchanged bilaterally and scattered across systems — slow, and a single stale instruction can send funds to the wrong account. A shared directory keeps them in one validated place.
COMMON CONFUSION
“A Standing Settlement Instruction is a signed legal agreement to settle in a particular way.”
An SSI is routing and settlement data held on file — the where and how of settling a currency — not necessarily a bilateral legal contract. It tells operations where to send funds; the underlying account relationship and any agreement between the parties are separate matters. Treat an SSI as reliable settlement detail to be kept current, not as proof of a legal arrangement.
Reachability, and permission to message
Knowing the institution and where to settle still leaves two questions. For euro scheme payments, the SEPA (Single Euro Payments Area) routing directory answers reachability: whether a given institution can actually receive a particular scheme payment, and by which route. An institution can exist, hold a valid BIC, and still not be reachable for a specific euro scheme. Separately, before two institutions exchange Swift messages there must be an authorisation between them, managed through the Relationship Management Application; RMA Plus is the granular form, where an authorisation can be scoped to specific message types rather than all-or-nothing. It is a defensive control — only expected message types arrive from expected partners, and permission can be withdrawn if a relationship changes.
Four questions, four directories
- Which institution?
- IBAN Plus derives the BIC from the account number
- Where to settle?
- The SSI Directory holds the standing settlement details
- Reachable?
- The SEPA routing directory confirms scheme reachability
- Permitted?
- RMA Plus confirms the message exchange is authorised
If all four checks pass, is the payment guaranteed to go through?
These four answer routing and permission — the right institution, the settlement details, reachability, and authorisation. They do not confirm the beneficiary account is open and in good standing, nor do they screen the parties. A payment normally needs all four to pass and the account and screening checks that sit alongside them. Each is a separate gate; clearing them all is what lets a payment pass straight through, but each still has to be cleared on its own.
STRICTLY SPEAKING
Strictly speaking, these directories describe structure, agreements-on-file, and permissions — not live account status. IBAN Plus tells you the institution; it does not confirm the account exists. An SSI tells you where to send funds; it does not prove a legal relationship. Reachability tells you a bank can receive a scheme payment today; it can change. Keep each current and they remove distinct, avoidable failures — but none of them is account verification or screening.
FOR NOW, REMEMBER
- IBAN Plus derives the correct BIC from an account number, removing a common misrouting cause when no institution code was supplied.
- The SSI Directory holds standing settlement details — routing and settlement data on file, not necessarily a bilateral legal agreement.
- The SEPA routing directory answers reachability; RMA Plus governs which message types are authorised between two institutions.
- Which institution, where to settle, whether reachable, whether permitted — four separate checks, and a payment normally needs all four plus account and screening controls.
TRY IT YOURSELF
Maya finds a current SSI on file for the supplier's bank in euro. A colleague says, "Good — that proves we have a settlement agreement in place with them." How should she respond?
These directories describe institutions, routes, and permissions. But before a bank agrees to move money for another at all, it must know who that counterparty is. Next: the shared registry where correspondent due-diligence data is collected once and reused.
KEEP GOINGKey takeaways / 03
Three things to remember
- 01
IBAN Plus derives the correct BIC from an IBAN to route accurately.
- 02
The SSI Directory records where and how counterparties settle each currency.
- 03
SEPA routing shows reachability and RMA Plus governs who may message whom.
Practical use cases / 04
Where you would use this
A payment system runs an IBAN through IBAN Plus to find the receiving institution's BIC before routing.
An operations team reads the SSI Directory to confirm the correct settlement account for a currency without contacting the counterparty.
A messaging team checks RMA Plus to confirm an authorisation exists before sending a new message type to a counterparty.
Worked example / 05
Put the idea into a real situation
Illustrative example: a fictional bank, Larkspur Financial, receives a EUR 12,500.00 payment instruction naming only the beneficiary IBAN DE00 0000 0000 0000 0000 00. It runs the IBAN through IBAN Plus, which derives the beneficiary institution's BIC. It then checks the SEPA routing directory, confirming the institution is reachable for euro payments, and settles using the account recorded in the SSI Directory. All three lookups complete before the payment is released.
Evidence & review / 07
Evidence & review
Swift's IBAN Plus, SSI Directory, SEPA routing directory, and RMA Plus, used for deriving institution codes, settlement routing, reachability, and messaging authorisation.
What this brief simplifies: Treats each directory as answering one clean question; production routing combines them with account and screening checks. IBAN structure and RMA scoping are described at teaching depth. SSIs are framed as settlement data on file, not legal agreements.
Sources for this brief2
- Market practice
SwiftRef reference data services ↗ — Swift
Used for public summaries of the SwiftRef directories and their delivery through files, a web application, and application programming interfaces.
- Simplified educational illustration
Payments Signal editorial teaching models — Payments Signal
Used wherever diagrams, scenarios, figures, or example values are didactic constructions rather than sourced facts; every such use carries a simplifications disclosure. All people, companies, banks, and list entries in examples are fictional.