What FIDEL API does

Fidel API (trading as Fidel, legally Enigmatic Smile Ltd) is a London-headquartered financial infrastructure platform that provides APIs for developers to link payment cards to applications and capture real-time transaction data. The company's core product, the Select Transactions API, delivers enriched transaction records from partner merchants typically within seconds of authorization events, enabling event-based user experiences; an Offers API add-on module extends the platform to create, manage, and track card-linked offers for loyalty and promotional programs. The platform is engineered around a proprietary tokenization engine that never stores card numbers, Card Enrollment SDKs that abstract PCI compliance from developers, TLSv1.2 end-to-end encryption, webhook-based event delivery, versioned API changes, and a 99.99% uptime SLA.

The business operates a developer-first, API-first go-to-market motion with a freemium self-serve tier for individual developers and a direct sales motion for enterprise customers, generating revenue through usage-based pricing tied to API call and transaction volume. Fidel API serves three primary use cases: rewards and loyalty programs (case studies include Avios and Perkbox), attribution and customer insights, and payments/fintech applications (case study: Google Pay). Distribution combines a self-serve dashboard, detailed documentation, sample apps, GitHub presence, and active social channels with enterprise sales engagement.

The company has raised approximately $86 million across multiple funding rounds from 2014 through April 2022, including a $65 million Series B led by Bain Capital Ventures with participation from Citi Ventures, Hedosophia, Nyca Partners, QED Investors, RBC Capital, Bossa Invest, and Commerce Ventures. The company employs 101-250 people, operates globally from London, and is led by CEO Salman Syed with founder Dev Subrata; leadership includes VPs across global strategic initiatives, emerging products and payments, engineering, and customer support, plus a chief revenue officer.

Name

FIDEL API

Legal name

Enigmatic Smile Ltd

Website

https://fidelapi.com

Company type

Private

Founded year

2013

Operating status

Operating

Headcount range

11–50 employees

Short description

Fidel API is a London-based financial infrastructure platform providing APIs that let developers link payment cards to applications and capture real-time transaction data for loyalty, attribution, and fintech use cases globally.

Ownership category

akta.pro rank

Product category

Card-Linked Financial Infrastructure API

akta.pro primary industry

Payment Gateways & API Connectivity (FSAGABAB)

Keywords

• Card-linked APIs
• Transaction data infrastructure
• Real-time payment APIs
• Developer financial APIs
• Card enrollment SDKs

Headquarters

HQ city

London

HQ country

United Kingdom

HQ region

Europe

Offices1 record

Markets served

GTM type

B2B

Offering type

Software

Cost components

Technology or R&D, Personnel, Operations, Marketing or Sales, Infrastructure

Revenue model

1. API Usage/Transaction Fees: Usage-based pricing model where developers pay based on API usage, likely per transaction or API call volume. This aligns with the transaction-based nature of the platform capturing card transactions in real-time.

Pricing tiers

Go-to-market motion3 records

Distribution channels2 records

Marketing channels8 records

Core offering

Fidel API provides a unified financial infrastructure API platform that lets developers link bank cards to applications globally and capture enriched, real-time transaction records from partner merchants. Its core Select Transactions API streams transaction authorization messages within seconds, while the Offers API add-on enables creation, management, and tracking of card-linked offers for rewards, loyalty, and attribution use cases.

Product overview

Fidel API is a unified API platform that enables developers to link bank cards to applications globally, creating programmable money experiences. The platform consists of two main products: the Select Transactions API (core product) providing enriched, real-time transaction records from partner merchants, and the Offers API (add-on module) for creating, managing, and tracking card-linked offers. Together they enable real-time payment event-driven experiences for use cases including rewards programs and attribution/insights.

Differentiator

Problem solved

Functional benefit

Products and services

• Select Transactions API Core API product that provides enriched, real-time transaction records from partner merchants, enabling developers to securely connect to users' cards, capture purchases in real time, and trigger event-based experiences when transactions occur. Targets developers building programmable money experiences.
• Offers API Add-on module that enables developers to create, manage, and track card-linked offers. Builds on the Select Transactions API to power loyalty, promotional, and card-linked offer programs for businesses.

Quantifiable outcome

• 12x growth in card-linked members for Avios
• +2 more outcomes

Named customers3 records

Segments3 records

Ideal customer profiles4 records

Technology focussed Yes

API detail

Has API

Yes

API docs

API detail

Core technology

AI maturity

App detail

Feature6 records

Partnerships

One partnership is on record.

• Google PayflagshipTechnology or IntegrationFeatured case study partner showcasing how Google Pay uses Fidel API to reimagine merchant and end-user experiences on the platform. A dedicated video demonstrates Fidel API in action with Google Pay.

Scale indicators3 records

Recent moves4 records

Expansion highlights6 records

Direct peers

• Plaid: Plaid is a developer-first financial data connectivity platform offering account-linking APIs that let developers access bank transaction data. It is the most directly comparable peer to Fidel API given shared developer-first GTM, API infrastructure model, and overlap in serving fintech, payments, and loyalty use cases — though Plaid focuses on bank-account aggregation rather than card-network authorization events.
• TrueLayer: TrueLayer is a London-based open banking API platform providing PSD2-compliant connectivity to bank accounts across Europe. It is comparable to Fidel API as a UK-headquartered developer-first financial infrastructure platform with an API-first GTM and horizontal use cases in payments, lending, and fintech — though it focuses on A2A/open-banking rather than card-linked data.
• Cardlytics: Cardlytics operates a card-linked advertising and offers platform that leverages bank-card transaction data to deliver targeted promotions. It is directly comparable to Fidel API's Offers API use case (card-linked offers, rewards, loyalty), competing for the same end customers in the card-linked space, though Cardlytics focuses on advertising-driven monetization rather than developer infrastructure.
• Button: Button provides a mobile commerce optimization API, including card-linking and affiliate routing infrastructure for apps. It is a direct peer to Fidel API in the card-linking-for-developers category, serving similar fintech and commerce customers with comparable developer-first distribution and API-first architecture.
• Tink: Tink is a European open banking platform (acquired by Visa) offering account aggregation, payment initiation, and financial data APIs. It is comparable to Fidel API as a fintech API infrastructure provider serving banks, fintechs, and developers across Europe, though it specializes in open-banking connectivity rather than card-network authorization data.

Broad incumbents

• MX Technologies: MX Technologies provides a broad financial data platform offering aggregation, analytics, and money management APIs to financial institutions and fintechs. It is comparable to Fidel API as a financial data API infrastructure player, but operates at a larger scale with deeper FI relationships and a wider product portfolio that goes beyond card-linked data into full account aggregation.
• Finicity: Finicity is a financial data aggregation platform (acquired by Mastercard) providing open-banking and financial-data APIs to lenders, fintechs, and banks. It is comparable to Fidel API as a card-and-account data infrastructure provider, but is now embedded within Mastercard, giving it strategic distribution that an independent platform like Fidel must compete against.
• Yodlee: Yodlee (an Envestnet company) is one of the longest-standing financial data aggregation platforms, serving banks and fintechs with account-data and transaction-categorization APIs. It is comparable to Fidel API in the transaction-data infrastructure category, though Yodlee is an established incumbent with a much broader data set and enterprise customer base.

Emerging players

• Akoya: Akoya is a financial data-access network that provides a single API for consumer-permissioned access to bank account data across multiple institutions. It is comparable to Fidel API as a developer-facing financial data connectivity layer, though Akoya's bank-direct data model positions it as more of an open-banking aggregator than a card-network-data specialist.

Regional players

• Basiq: Basiq is an Australia-based open banking data aggregation platform offering APIs for accessing bank transaction data under the CDR regime. It is comparable to Fidel API as a developer-first financial data infrastructure player, but is regionally focused on Australia and does not directly compete in Fidel's core UK/US/EU markets.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat4 records

Key risks6 records

Key highlights6 records

Customer concentration

• Xx.com/fidelhq
• GitHubgithub.com/Enigmatic-Smile
• LinkedInlinkedin.com/company/fidel-api
• Facebookfacebook.com/fideluk

Revenue estimate

Valuation estimate

Number of profiles

Profiles1 record

Funding overview

Funding rounds6 records

Investors13 records

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about FIDEL API