What technology stack does Citizens run its AI on?
Citizens runs on public cloud: CIO Michael Ruttledge says it is 'the first super-regional bank to move its entire mainframe and every business application into the cloud', after migrating 700 applications in four years, and the 2025 Annual Review says it became fully cloud-based in 2025. Business applications sit in AWS and Microsoft Azure, linked through Equinix; the mainframe moved to Kyndryl zCloud and the core is being upgraded with FIS. Data runs through an enterprise data cache on MongoDB Atlas on AWS that, according to AWS, holds core data for 14 million customers and saved $1.5 million a year, with 99.99% uptime. The cloud move closed 25 data centres, cut infrastructure cost 10% to 15% and incidents 78%. Generative AI is part of the migration: it rewrote a mortgage system of millions of lines in six weeks, and Citizens reports code-conversion and testing gains of 10% to 20% (2024) and engineers 30% to 40% more productive (2026). Models come from providers through an internal portal (OpenAI, AWS Bedrock, Anthropic), and an AI-first Innovation Hub with Infosys adds engineering capacity. Technology spending and engineering headcount are not disclosed.[1][2][3][4][5][6][7][8]
Data as of Oct 16, 2026 · Citizens profile updated Oct 13, 2026 · 24 sources cited on this page · 140 banks profiled on this site · Markdown
What are the layers of Citizens' technology stack?
Each layer as Citizens or its vendors describe it. Vendor-published pages are attributed to the vendor.
| Layer | What Citizens uses | Detail | Source date |
|---|---|---|---|
| Public cloud | AWS and Microsoft Azure | Every business application migrated; 700 applications in four years; Oracle Cloud Infrastructure also named in 2025 | 2025-2026[1][9] |
| Network | Equinix | Networking hub connecting to AWS and Azure | December 2025[3] |
| Mainframe and core | Kyndryl zCloud; FIS | Mainframe moved to Kyndryl's cloud; core upgrade with FIS | December 2025[3] |
| Data cache | MongoDB Atlas on AWS, with AWS Lambda, Amazon EKS and Amazon Redshift | Per AWS: 14 million customers' core data loaded in under 40 minutes; 99.99% uptime; 30 ms responses for 95% of requests; $1.5 million a year saved | 2026[4] |
| Mainframe data integration | Precisely | Per AWS, near real-time trusted data across channels and a large cut in MIPS usage | September 2026[10] |
| Fraud platform | MongoDB Atlas on AWS | Cloud fraud-management platform handling about 80% of claims volume since 2023 | February 2025[9] |
| Model access | Internal gen-AI portal: OpenAI, AWS Bedrock, Anthropic | No in-house LLM; some models hosted inside the bank's VPC | 2024-2026[6][3][11] |
| Developer tools | Microsoft Copilot, GitHub Copilot and its coding agent | About 800 developers; engineers moving to supervise multiple agents | 2025-2026[5][7] |
| Contact centre | Amazon Connect | Voice agents built into the mobile app, per AWS | September 2026[12] |
| Engineering capacity | Infosys, AI-first Innovation Hub | Infosys Topaz (2025) and Topaz Fabric (2026) for AI-led platforms and data-centre exit | 2025-2026[13][8] |
What has Citizens reported from its cloud and AI engineering work?
Citizens closed 25 data centres and reports infrastructure costs down 10% to 15%, incidents down 78% and about $45 million of annualised savings from the cloud move.[3][1]
Generative AI converts legacy code: a mortgage system with millions of lines was rewritten and moved in six weeks. Engineering output rose 10% overall and 55% for engineers on advanced agents by June 2026, and AI coding pilots showed gains from 30% to 10x.[5][1][14]
AWS's MongoDB case study quotes Vinod Yadav, unit CIO for core banking, lending and operations technology, saying the always-on data cache lets the bank 'increase developer velocity and the speed at which we bring new features to market'.[4]
What does the Citizens profile record on this topic?
The rows below are the entries of the Citizens AI strategy profile that bear on this page, as of Oct 13, 2026; the profile holds the full record of 35 dated moves, 20 use cases and 50 sources.
| Use case | What the record shows | Status | Source |
|---|---|---|---|
| Coding agents | GitHub Copilot's agent for ~800 developers; +55% output for advanced-agent users. | In production | [5][1] |
| Legacy code conversion | Gen AI rewrites old code for the cloud; mortgage system in six weeks. | In production | [5] |
| Agentic fraud-claims and AML checks | Fraud platforms rebuilt in the cloud with machine learning for suspicious-activity reports and security checks; agentic AI piloted for straight-through processing of small-dollar claims, with AML checks to follow. | Pilot | [3][9] |
| Engineers as supervisors of coding agents | Citizens is moving engineers from writing code to managing code-writing agents; average engineer productivity up 30% to 40% in a year. | Rolling out | [15][7] |
| Vendor consolidation and outsourcing exit | Outsourced call-centre and engineering contracts to be shed first; one customer-chat platform to replace several; over $30 million of vendor savings projected for 2026. | Rolling out | [15][16] |
| Models hosted inside the bank's VPC | For some use cases Citizens runs models in its own cloud network so nothing leaves its firewall, trading engineering effort for control. | In production | [11] |
| Date | Move | Detail | Source |
|---|---|---|---|
| Sep 29, 2026 | Coughlin: engineers now 30-40% more productive with AI | American Banker reports the average Citizens engineer is 30% to 40% more productive than a year earlier under the three-year, $300 million Reimagine the Bank project; Coughlin says the role is evolving toward engineers overseeing multiple AI agents, and that AI-existential-risk warnings have 'not really' changed the project's direction. | [7] |
| Jul 30, 2026 | CDAO Swamy: LLMs as a translator for customer intent; models inside the bank's VPC | On an American Banker panel Krish Swamy said LLMs map what callers say to a small set of intents, that some models run inside Citizens' own VPC, that chatbots answer questions but do not yet execute transactions, and that commercial underwriters share a Copilot prompt library. | [11] |
| Jul 16, 2026 | Q2 2026: AI agents in the back office, a 10x engineering pilot | Back-office re-architecture with AI agents orchestrating end-to-end workflows, AI case classification, AI in credit-card contact centres and a first enterprise-wide AI-chat agent; about $7 million of program costs in the quarter. | [17][18][19][20][21] |
| Jun 1, 2026 | The mainframe goes: CIO's cloud-first claim | 700 applications migrated; CiZi −44% call volume; +55% output for engineers on advanced agents. | [1] |
| Mar 3, 2026 | 2025 Annual Review: first super-regional fully in the cloud; CiZi use up 40% | The shareholder review says Citizens became the first super-regional bank fully in the cloud in 2025, set up a transformation office for Reimagine the Bank, and that CiZi usage rose 40% year over year in 4Q25. | [2] |
| Nov 20, 2025 | GitHub Copilot's coding agent to ~800 developers | Half the software developers; fintech partners rewriting legacy systems for the cloud. | [5] |
| Aug 6, 2025 | 'First inning' of AI in business banking | AI not yet in the online banking platform; exploring applications, per the head of business banking. | [22] |
| Mar 12, 2025 | Infosys collaboration widened to AI-led transformation | Infosys said it would use its Topaz AI offering to help Citizens build cloud-native platforms and exit its data centres; the two had worked together for five years. | [13] |
| Feb 27, 2025 | Fraud platform rebuilt in the cloud with new models | A head of fraud risk said the cloud fraud-management platform on MongoDB Atlas on AWS had handled about 80% of claims volume since 2023, and that new detection models beat the industry detection rate; more than 80% of applications were in the cloud. | [9] |
| Sep 9, 2024 | No in-house LLM: AWS and Microsoft models | Ruttledge said Citizens had no plan to build its own large language models and would use best-in-class models from its providers; gen AI for documentation, code conversion and testing gave a 10% to 20% productivity gain. | [6] |
| Jul 26, 2024 | CIO: 90 gen-AI ideas, six pursued, two in production; Copilot pilot lifts productivity 20% | A hackathon produced over 90 ideas. The two live uses were Microsoft Copilot for engineers (pilot showed a 20% productivity boost; rollout to about 1,000 engineers planned) and a gen-AI product assistant for contact-centre staff. A human validates the code and the answers. | [23] |
| Jun 4, 2024 | Van Saun: 'you have to walk before you run' with AI | At a Bernstein conference the CEO said Citizens was putting policies and governance in place first, called customer bots 'pretty advanced', and named code assistance and fraud detection as other targets. | [24] |
Is Citizens fully in the cloud?
Yes, by its own account. CIO Michael Ruttledge said in 2026 that Citizens is the first super-regional bank to move its entire mainframe and every business application into the cloud, after migrating 700 applications in four years, and the 2025 Annual Review says Citizens became the first super-regional fully in the cloud in 2025.
Which cloud providers does Citizens use?
Amazon Web Services and Microsoft Azure are its two main public clouds, connected through Equinix; Oracle Cloud Infrastructure was also named in 2025. The mainframe moved to Kyndryl's zCloud, and the core banking system is being upgraded with FIS.
How does Citizens use AI in software engineering?
About 800 developers, half its software engineers, use GitHub Copilot, some with its coding agent, and generative AI converts legacy code for the cloud, including a mortgage system rewritten in six weeks. President Brendan Coughlin said in September 2026 that the average engineer is 30% to 40% more productive than a year earlier.
What data platform does Citizens use?
AWS describes an enterprise data cache on MongoDB Atlas that holds core data for Citizens' 14 million customers, built with AWS Lambda, Amazon EKS and Amazon Redshift, and credits it with $1.5 million a year of savings. The same database runs under the bank's cloud fraud-management platform.
- Citizens Financial's Michael Ruttledge is #43 on the Most Innovative People in Finance ranking
- 2025 Annual Review
- Inside Citizens' plan to reimagine itself with AI
- Citizens Bank Partners with MongoDB and AWS to Reduce Costs by $1.5M
- How Citi, Citizens, TD deploy AI agents without upsetting humans
- Citizens sees up to 20% efficiency gains through gen AI
- Tech leaders say AI could end humanity. Banks still love it
- Revenue crosses $20 billion mark with resilient growth of 3.1% in FY 26 in constant currency (Client Wins: Citizens AI-first Innovation Hub)
- Citizens on pace for 100% cloud migration by Q3
- Citizens Bank Modernizes its Mainframe with AWS Partner Precisely
- The AI-Enabled Bank: Reimagining Retail Banking from Branch to Mobile
- Customer Contact Week Sessions On Demand: How Citizens Bank is building the AI-native customer experience
- Infosys Announces Expansion of Strategic Collaboration with Citizens to Propel AI-led Transformation
- Citizens Financial Group, Inc. Q1 2026 Earnings Call Summary
- Citizens' Coughlin talks 'overwhelming' pace of AI change
- Citizens (CFG) Q1 2026 Earnings Call Transcript
- 2Q26 Earnings Presentation (Form 8-K, Exhibit 99.2)
- Citizens Financial Group Q2 Earnings Call Highlights
- Citizens Bank Mobilizes AI to Target $450 Million Operational Savings by 2028
- Citizens to exit in-store branches, build standalones nearby
- Citizens Financial (CFG) Q2 2026 Earnings Call Transcript
- Small businesses turn to financial advice, data for growth: Citizens survey
- Citizens CIO: 'Human in the loop' still key for banks using genAI
- Citizens CEO: 'You have to walk before you can run' with AI
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