External Regulatory Circular DSP-465 of March 6, 2026, Subject 18: Interoperability of Immediate Low-Value Payment Systems

Bank of the Republic Board of Directors Bulletin Number: 8 Date: March 6, 2026 Pages: 19 Content • External Regulatory Circular DSP-465 of March 6, 2026, Subject 18: Interoperability of Immediate Low-Value Payment Systems. This bulletin is published in development of what is provided in letter a) of article 51 of Law 31 of 1992 and the paragraph of article 108 of Law 510 of 1999. Board of Directors Secretariat – Carrera 7 14 78, sixth floor – Bogotá, D. C. – Telephone: +57 (601) 484-9980

Document No: OT/PF/MAR/2026/123685 Recipients: Entities Administering Low-Value Payment Systems that process services of payment orders and/or immediate fund transfers, Superintendencia Financiera de Colombia and Superintendencia de la Economía Solidaria. EXTERNAL REGULATORY CIRCULAR DSP-465 PAYMENT SYSTEMS DEPARTMENT MANUAL Date: Friday, March 6, 2026 Subject 18: Interoperability of Immediate Low-Value Payment Systems. Annex 5 of External Regulatory Circular DSP-465 of May 15, 2025, corresponding to Subject 18: INTEROPERABILITY OF IMMEDIATE LOW-VALUE PAYMENT SYSTEMS, is modified. The changes are made in order to clarify and add: • Guidelines for the handling of error codes in the Compensation and Settlement of Immediate Payment Orders and/or Fund Transfers, and • the terms and conditions for failure event notifications to Clients. What is established in numeral 2.2.3 of Annex 5 must be complied with no later than two (2) months after the publication of this Circular. This Circular enters into force from its publication. Cordially, MARCELA OCAMPO Executive Manager DIONISIO VALDIVIESO BURBANO Deputy Manager of Payment Systems and Banking Operations

Document No: OT/PF/MAR/2026/123685 Page 18-A5-1 EXTERNAL REGULATORY CIRCULAR DSP-465 Date: Friday, March 6, 2026 Subject 18: Interoperability of Immediate Low-Value Payment Systems. Annex 5 Operational and Messaging Standards for the Processing of Immediate Payment Orders and/or Fund Transfers (PO/FT)

1. Times 1.1. Terms and conditions for the registration, control and standard of Timestamps for the Compensation and Settlement of Immediate PO/FT 1.1.1. The clocks of the systems of the Immediate Low-Value Payment System Administrating Entities (EASPBVI) and their Participants responsible for processing an Immediate PO/FT, must maintain permanent synchronization with the Legal Time service of the National Institute of Metrology of Colombia (INM). The EASPBVI and their Participants must use the domains provided by the INM for synchronization. 1.1.2. Timestamps must contain the date and time of the system processing the Immediate PO/FT, using the clock synchronized with the INM Legal Time service and be registered under the ISO 8601 standard in local time and in the YYYY-MM-DDThh:mm:SS.sss format. In this sense, the timestamp will include year; month; day; “T”, hour; minutes; seconds; tenths, hundredths and thousandths of a second. 1.1.3. In each new message generated within the flow of compensation and settlement of an Immediate PO/FT, the EASPBVI and Participants must preserve the timestamp information coming from the immediately preceding received message. Likewise, the EASPBVI and Participants will add the corresponding new timestamps. 1.1.4. When the ISO20022 standard is used in messaging for the compensation of Immediate PO/FT, timestamps must be incorporated according to the technical specifications defined by the Bank of the Republic in External Operational and Services Circular DSP-471 Subject 20: Regulation of the Operational Mechanism for Settlement (MOL) or those that modify or replace it.

Document No: OT/PF/MAR/2026/123685 Page 18-A5-2 EXTERNAL REGULATORY CIRCULAR DSP-465 Date: Friday, March 6, 2026 Subject 18: Interoperability of Immediate Low-Value Payment Systems. 1.1.5. In the case where a standard other than ISO20022 is used in connections between Participants and EASPBVI, the EASPBVI must guarantee that timestamps are incorporated in the messaging. 1.1.6. EASPBVI and their Participants must include names and timestamps in the messaging as indicated below: Timestamps for an Intra-SPBVI Immediate PO/FT prior to the entry into operation of the Operational Mechanism for Settlement Mark Timestamp name to add in messaging Description Responsible for adding timestamp in messaging t0’ T110 Originator Participant receives payment instruction confirmation from the Ordering Client Originator Participant t1 T120 Originator Participant sends payment instruction to EASPBVI after having applied the authorization activities of the Immediate PO/FT Originator Participant t1’ T210 EASPBVI receives payment instruction from Originator Participant EASPBVI t2 T220 EASPBVI sends payment instruction to Receiving Participant EASPBVI t2’ T310 Receiving Participant receives payment instruction from EASPBVI Receiving Participant t3 T320 Receiving Participant sends payment instruction to EASPBVI Receiving Participant t3’ T230 EASPBVI receives confirmation from Receiving Participant EASPBVI t4 T240 EASPBVI sends fund settlement confirmation to Originator Participant EASPBVI t4’ T130 Originator Participant receives fund settlement confirmation from EASPBVI Originator Participant t5 T140 Originator Participant sends message to Ordering Client confirming the debit of resources in their Payment Medium Originator Participant

Document No: OT/PF/MAR/2026/123685 Page 18-A5-3 EXTERNAL REGULATORY CIRCULAR DSP-465 Date: Friday, March 6, 2026 Subject 18: Interoperability of Immediate Low-Value Payment Systems. Timestamps for an Intra-SPBVI Immediate PO/FT after the entry into operation of the Operational Mechanism for Settlement Mark Timestamp name to add in messaging Description Responsible for adding timestamp in messaging t0’ T110 Originator Participant receives payment instruction confirmation from the Ordering Client Originator Participant t1 T120 Originator Participant sends payment instruction to EASPBVI after having applied the authorization activities of the Immediate PO/FT Originator Participant t1’ T210 EASPBVI receives payment instruction from Originator Participant EASPBVI t2 T213 EASPBVI sends payment instruction to Operational Mechanism for Settlement EASPBVI t2’ T510 Operational Mechanism for Settlement receives payment instruction from EASPBVI for fund reservation Operational Mechanism for Settlement t3 T520 Operational Mechanism for Settlement sends validated payment instruction to EASPBVI Operational Mechanism for Settlement t3’ T215 EASPBVI receives validated payment instruction from Operational Mechanism for Settlement EASPBVI t4 T220 EASPBVI sends payment instruction to Receiving Participant EASPBVI Compensation Settlement 3. Compensate and send payment instruction

1. Authorize and send payment instruction [success message] [success message]
2. Execute risk controls
3. Execute settlement 7b. Credit funds 7a. Debit funds Risk controls for acceptance 6a. Confirmation
4. Send ack message Acceptance 6b. Confirmation PREVIOUS PROCESSES:
5. Application of SPBVI rule to secure Originator Participant resources
6. Client fund reservation
7. Prior key resolution 4a. Validate account status 4b. Validate amount t5’ t0 t1 t1’ t2’ t4’ t0’ t3’ t3 t2 t4 t5 Time-out application zone (45s)

Document No: OT/PF/MAR/2026/123685 Page 18-A5-4 EXTERNAL REGULATORY CIRCULAR DSP-465 Date: Friday, March 6, 2026 Subject 18: Interoperability of Immediate Low-Value Payment Systems. t4’ T310 Receiving Participant receives payment instruction from EASPBVI Receiving Participant t5 T320 Receiving Participant sends payment instruction to EASPBVI Receiving Participant t5’ T230 EASPBVI receives confirmation from Receiving Participant EASPBVI t6 T233 EASPBVI sends confirmation to Operational Mechanism for Settlement EASPBVI t6’ T530 Operational Mechanism for Settlement receives confirmation from EASPBVI Operational Mechanism for Settlement t7 T540 Operational Mechanism for Settlement sends payment settlement confirmation to EASPBVI Operational Mechanism for Settlement t7’ T235 EASPBVI receives settlement confirmation from Operational Mechanism for Settlement EASPBVI t8 T240 EASPBVI sends fund settlement confirmation to Originator Participant EASPBVI t8’ T130 Originator Participant receives fund settlement confirmation from EASPBVI Originator Participant t9 T140 Originator Participant sends message to Ordering Client confirming the debit of resources in their Payment Medium Originator Participant

Document No: OT/PF/MAR/2026/123685 Page 18-A5-5 EXTERNAL REGULATORY CIRCULAR DSP-465 Date: Friday, March 6, 2026 Subject 18: Interoperability of Immediate Low-Value Payment Systems. Timestamps for an Inter-SPBVI Immediate PO/FT after the entry into operation of the Operational Mechanism for Settlement Mark Timestamp name to add in messaging Description Responsible for adding timestamp in messaging t0’ T110 Originator Participant receives payment instruction confirmation from the Ordering Client Originator Participant t1 T120 Originator Participant sends payment instruction to Originator SPBVI after having applied the authorization activities of the Immediate PO/FT Originator Participant t1’ T210 Originator SPBVI receives payment instruction from Originator Participant Originator SPBVI t2 T213 Originator SPBVI sends payment instruction to Operational Mechanism for Settlement Originator SPBVI t2’ T510 Operational Mechanism for Settlement receives payment instruction request from Originator SPBVI for fund reservation Operational Mechanism for Settlement t3 T520 Operational Mechanism for Settlement sends payment instruction to Receiving SPBVI Operational Mechanism for Settlement t3’ T410 Receiving SPBVI receives payment instruction from Operational Mechanism for Settlement Receiving SPBVI t4 T420 Receiving SPBVI sends payment instruction to Receiving Participant Receiving SPBVI t4’ T310 Receiving Participant receives payment instruction from Receiving SPBVI Receiving Participant t5 T320 Receiving Participant sends payment instruction to Receiving SPBVI Receiving Participant t5’ T430 Receiving SPBVI receives confirmation from Receiving Participant Receiving SPBVI t6 T440 Receiving SPBVI sends confirmation to Operational Mechanism for Settlement Receiving SPBVI t6’ T530 Operational Mechanism for Settlement receives confirmation from Receiving SPBVI Operational Mechanism for Settlement t7 T540 Operational Mechanism for Settlement sends settlement confirmation to Originator SPBVI Operational Mechanism for Settlement t7’ T235 Originator SPBVI receives confirmation from Operational Mechanism for Settlement Originator SPBVI

Document No: OT/PF/MAR/2026/123685 Page 18-A5-6 EXTERNAL REGULATORY CIRCULAR DSP-465 Date: Friday, March 6, 2026 Subject 18: Interoperability of Immediate Low-Value Payment Systems. t8 T240 SPBVI sends fund settlement confirmation to Originator Participant Originator SPBVI t8’ T130 Originator Participant receives confirmation from Originator SPBVI Originator Participant t9 T140 Originator Participant sends message to Ordering Client confirming the debit of resources in their Payment Medium Originator Participant 1.2. Maximum time for the value promise to the Client 1.2.1. Regarding compliance with the 20 seconds for 99.5% of Immediate PO/FT originated in the SPBVI referred to in letter d) of numeral 5.1 of this Circular, EASPBVI must consider the following parameters: 1.2.1.1. The initial and final timestamps for Immediate PO/FT will be the following: Flow Initial Point Final Point Intra-SPBVI Operation prior to entry into operation of the Operational Mechanism for Settlement t0’ / Timestamp T110 t5 / Timestamp T140 Intra-SPBVI Operation after entry into operation of the Operational Mechanism for Settlement t0’ / Timestamp T110 t9 / Timestamp T140 Compensation Settlement 3. Compensate and send payment instruction [success message] 6. Send validated payment instruction 7a. Validate account status 7b. Validate amounts 8a. Confirmation [success message] 12a. Debit funds 4a. Operational validations 4b. Reserve funds

1. Send payment instruction Risk controls for acceptance
2. Execute risk controls Acceptance 12b. Credit funds 8b. Confirmation 11a. Debit confirmation 10a. Settlement confirmation
3. Route validated payment instruction 10b. Settlement confirmation Time-out application zone (45s) 8c. Confirmation t0 t0’ t1 t1’ t2’ t2 t3’ t3 t4 t4’ t5’ t5 t6’ t6 t7’ t7 t8’ t8 t9’ t9 PREVIOUS PROCESSES:
4. Resource assignment by Originator Participant in MOL
5. Client fund reservation
6. Prior key resolution

Document No: OT/PF/MAR/2026/123685 Page 18-A5-7 EXTERNAL REGULATORY CIRCULAR DSP-465 Date: Friday, March 6, 2026 Subject 18: Interoperability of Immediate Low-Value Payment Systems. Inter-SPBVI Operation after entry into operation of the Operational Mechanism for Settlement t0’ / Timestamp T110 t9 / Timestamp T140 1.2.1.2. Its calculation must be performed on a weekly basis for all operations completed between Monday and Sunday. 1.2.1.3. For Intra-SPBVI operations in order to guarantee compliance with 20 seconds in 99.5% of operations, EASPBVI may define with their Participants Service Level Agreements on intermediate times. 1.2.1.4. EASPBVI must conserve and store as a minimum weekly descriptive statistics associated with the calculation of total times and intermediate times of the Compensation and Settlement flow of Immediate Payment Orders and/or Transfers. 1.3. Time-out of the Compensation and Settlement process 1.3.1. The Time-out applicable to the processing of an Immediate PO/FT corresponds to forty-five (45) seconds. It applies from the moment the Originator Participant receives confirmation of the Immediate PO/FT from the Ordering Client (timestamp t0’ / T110) until the moment the EASPBVI has received the first confirmation from the Operational Mechanism for Settlement, prior to the acceptance of the Immediate PO/FT by the EASPBVI. 1.3.2. The Time-out applicable to the processing of the Immediate PO/FT must be controlled in real time by the Originator SPBVI, the Operational Mechanism for Settlement and the Receiving SPBVI, according to the technical specifications defined by the Bank of the Republic in External Operational and Services Circular DSP-471 Subject 20: Regulation of the Operational Mechanism for Settlement (MOL) or those that modify or replace it. 1.3.3. When the defined Time-Out is met for any of the steps in the flow of Compensation and Settlement of an Immediate PO/FT, the Originator SPBVI, the Operational Mechanism for Settlement, or the Receiving SPBVI, as applicable, must inform this Time-Out in the flow responses. The EASPBVI and its Participants in each exception case may send a PACS.028 query message to the Operational Mechanism for Settlement in order to know the status of the transaction, according to the technical specifications

Document No: OT/PF/MAR/2026/123685 Page 18-A5-8 EXTERNAL REGULATORY CIRCULAR DSP-465 Date: Friday, March 6, 2026 Subject 18: Interoperability of Immediate Low-Value Payment Systems. defined by the Bank of the Republic in External Operational and Services Circular DSP-471 Subject 20: Regulation of the Operational Mechanism for Settlement (MOL) or those that modify or replace it. 1.3.4. When the Time-out is declared by the EASPBVI, it must notify its Participants and the Operational Mechanism for Settlement according to the technical specifications defined by the Bank of the Republic in External Operational and Services Circular DSP-471 Subject 20: Regulation of the Operational Mechanism for Settlement (MOL) or those that modify or replace it. The Originator Participant must notify the Ordering Client immediately, indicating at minimum that the transaction could not be completed due to exceeding the maximum processing time. 1.4. Terms and conditions for the registration, control and standard of Timestamps related to the registration of Keys in Directories and other events relative to their use 1.4.1. The clocks of the systems of the EASPBVI and their Participants responsible for Key management and resolution processes must maintain permanent synchronization with the Legal Time service of the National Institute of Metrology of Colombia (INM). The EASPBVI and their Participants must use the domains provided by the INM for synchronization. 3. Compensate and send payment instruction 6. Send validated payment instruction 7a. Validate account status 7b. Validate amounts 8a. Confirmation 4a. Operational validations 4b. Reserve funds

1. Authorize and send payment instruction Risk controls for acceptance
2. Execute risk controls 8b. Confirmation
3. Route validated payment instruction 8c. Confirmation

Time-out application zone (45s) [success message] [success message] 9. Execute settlement 11b. Confirm credit 12b. Credit funds 11a. Debit confirmation 10a. Settlement confirmation 10b. Settlement confirmation PACS.028 query message PACS.002 response message Compensation Settlement Total transaction time up to 20 seconds

Document No: OT/PF/MAR/2026/123685 Page 18-A5-9 EXTERNAL REGULATORY CIRCULAR DSP-465 Date: Friday, March 6, 2026 Subject 18: Interoperability of Immediate Low-Value Payment Systems. 1.4.2. Timestamps must contain the date and time of the system managing Key management and resolution processes, using the clock synchronized with the INM Legal Time service and be registered under the ISO 8601 standard in local time and in the YYYY-MM-DDThh:mm:SS.sss format. In this sense, the timestamp will include year; month; day; “T”, hour; minutes; seconds; tenths, hundredths and thousandths of a second. 1.4.3. Timestamps related to Key management and resolution processes in Federated Directories and the Centralized Directory must be incorporated in the messaging between Federated Directories and the Centralized Directory, according to the technical specifications defined by the Bank of the Republic in External Operational and Services Circular DSP-470 Subject 19: Regulation of the Centralized Directory (DICE) or those that modify or replace it. 1.4.4. In connections between Participants and EASPBVI, EASPBVI must guarantee that Timestamps related to Key management and Resolution processes are incorporated in the messaging. 1.4.5. Timestamps for Key Resolution 1.4.5.1. Key resolution, which constitutes one of the previous processes to the flow of compensation and settlement of an Immediate PO/FT, must be executed in a maximum time of five (5) seconds counted from the moment the Participant receives the Key Resolution request from the Ordering Client, for 99.5% of Key Resolution requests. 1.4.5.2. The Time-out for Key resolution is ten (10) seconds and must be controlled by the EASPBVI and the Participant, according to the technical specifications defined by the Bank of the Republic in External Operational and Services Circular DSP-470 Subject 19: Regulation of the Centralized Directory (DICE) or those that modify or replace it. The measurement of the Time-out starts from the moment the Participant receives the Key Resolution request from the Ordering Client and ends at the moment

Document No: OT/PF/MAR/2026/123685 Page 18-A5-10 EXTERNAL REGULATORY CIRCULAR DSP-465 Date: Friday, March 6, 2026 Subject 18: Interoperability of Immediate Low-Value Payment Systems. the Participant receives the Resolution response from the Federated Directory. In case the Time-out materializes, the Participant must notify the Client immediately with a message that at minimum indicates that the Immediate PO/FT could not be processed. 1.4.5.3. EASPBVI and their Participants must store and collect Timestamps of the Key resolution process as presented below: Timestamps for Key resolution in the Federated Directory Mark Timestamp name Description Responsible for adding timestamp in messaging t0’ C110 Participant receives Key resolution request from Ordering Client Participant t1 C120 Participant sends Key resolution request to Federated Directory Participant t1’ C210 Federated Directory receives Key resolution request from Participant EASPBVI t2 C240 Federated Directory sends Key resolution response to Participant EASPBVI t2’ C130 Participant receives Key resolution response from Federated Directory Participant t3 C140 Participant notifies Client with response regarding Key resolution request Participant

Document No: OT/PF/MAR/2026/123685 Page 18-A5-11 EXTERNAL REGULATORY CIRCULAR DSP-465 Date: Friday, March 6, 2026 Subject 18: Interoperability of Immediate Low-Value Payment Systems. Timestamps for Key resolution in the Centralized Directory Mark Timestamp name to add in messaging Description Responsible for adding timestamp in messaging t0’ C110 Participant receives Key resolution request from Ordering Client Participant t1 C120 Participant sends Key resolution request to Federated Directory Participant t1’ C210 Federated Directory receives Key resolution request from Participant EASPBVI t2 C215 Federated Directory sends Key resolution request to Centralized