The United Illuminating Company Data Access Guide

The United Illuminating Company (UI), an Avangrid utility, provides electric distribution service to about 346,000 customers in southern Connecticut under the state's deregulated retail-choice market, regulated by PURA. UI offers a customer portal, Energy Analyzer with CSV/XML export, manual interval-data requests, and full supplier EDI (810/814/867), but has not implemented Green Button.

Connecticut · Investor-Owned Utility·345,877 customers·Fully supported by Nectar·Last updated June 3, 2026

How to Get Your The United Illuminating Company Data: All Access Methods

Method1st Party3rd PartyCustomer TypesData TypesLatencyFormat
Online Portal / Energy AnalyzerResidential, C&IBills, daily/monthly usageDaily (72hr initial setup)PDF / CSV / XML
Interval Data RequestC&I, suppliers15-min interval kWh7-10 business daysCSV / Excel
Customer Data / Historical Usage RequestC&I, consultants, aggregatorsMonthly usage, demand, load profile5-10 business daysCSV / Excel / PDF
EDI (810/814/867)Suppliers, aggregatorsEnrollment, invoice, usageBatch / automatedEDI X12
Green Button / Share My DataNoneNot implementedN/AN/A
01

Billing Data Access

UI provides billing data through the portal.uinet.com customer portal and the Energy Analyzer tool. Customers can view up to 24 months of bills and download consumption data in PDF, CSV, and XML. Third-party access to billing data runs through formal Customer Data Request and Historical Usage Request processes with customer authorization.

What Data Is on Your The United Illuminating Company Bill

  • Current and historical bills (PDF)
  • Daily and monthly consumption (kWh)
  • Demand readings (kW) for larger customers
  • Account balance and payment due dates
  • Rate schedule and load profile information

How to Download The United Illuminating Company Bills (Business & Commercial)

  1. 01Log in to portal.uinet.com and open Energy Analyzer
  2. 02Use facility comparison for multi-location accounts
  3. 03Export consumption in CSV or XML for analysis software
  4. 04For extended history or formal exports, email supplier.relations@uinet.com (5-10 business day turnaround)

How to Download The United Illuminating Company Bills (Residential)

  1. 01Register at portal.uinet.com using your account number and name key
  2. 02Wait up to 72 hours after account creation for Energy Analyzer data
  3. 03Open Energy Analyzer and select a date range
  4. 04Download consumption data as PDF, CSV, or XML
  5. 05View up to 24 months of bills under Billing > View Bill History

Third-Party Access to The United Illuminating Company Billing Data

Customer Data Request

  1. 01Obtain written customer authorization (LOA) specifying account, scope, and date range
  2. 02Complete UI's Customer Data Request form (from supplier.relations@uinet.com)
  3. 03Email form plus authorization to supplier.relations@uinet.com
  4. 04Receive CSV/Excel/PDF data within 5-10 business days

Historical Usage Request (Suppliers/Aggregators)

  1. 01Be a licensed supplier or registered aggregator (or authorized consultant)
  2. 02Submit a Historical Usage Request with customer authorization
  3. 03Specify customers, date ranges, and data types
  4. 04Receive monthly usage/demand exports (typically 5-10 business days; batches 7-15 days)
PDFCSVXMLExcel (via request)

Want to understand the charges on your bill?

See the The United Illuminating Company Rate Schedules & Tariff Guide →

02

Interval Data & Smart Meters

UI has deployed AMI smart meters capable of 15-minute interval reads. Interval data is not self-service; it is obtained through a signed Interval Data Request Service Agreement, processed within about 7 business days and delivered electronically. Energy Analyzer also provides granular daily consumption.

Meter Technology
Advanced Metering Infrastructure (AMI) with remote read; GE or similar smart meters.
Electric Granularity
15-minute interval reads when available (hourly in some cases), via manual request; daily consumption via Energy Analyzer.
Gas Granularity
Not applicable (electric distribution only).

How to Download The United Illuminating Company Interval Data via Green Button

  1. 01Green Button is not implemented at UI
  2. 02Confirm AMI/interval availability with customer service (800-722-5584)
  3. 03Submit an Interval Data Request Service Agreement to supplier.relations@uinet.com
  4. 04Receive CSV/Excel interval data (timestamp + kWh) within ~7-10 business days

Interval data is essential for rate comparison and TOU analysis.

See which The United Illuminating Company rate schedule is best for your usage pattern →

03

Green Button Access

Download My Data

UI has not implemented Green Button Download My Data. Customers instead export CSV/XML from Energy Analyzer or request interval data manually. (Connecticut peer Eversource does offer Green Button.)

Available To
Not available

Connect My Data

UI has not implemented Green Button Connect My Data / Share My Data. There is no OAuth-based third-party authorization portal; third-party access is via EDI or manual data requests.

API Standard
None
Available To
Not available

04

Third-Party API Access

UI does not offer a public REST/GraphQL developer API. Programmatic third-party access is via EDI for suppliers/aggregators and the Supplier Management System (SMS) self-service portal, plus manual Customer Data and Historical Usage Requests. Nectar provides API access to UI billing and interval data with customer authorization — see docs.nectarclimate.com.

Program
No public API (EDI + manual requests)
Auth Method
EDI trading-partner credentials / SMS portal login; no OAuth API.
Rate Limits
Not applicable (batch EDI / portal).
Interval Latency
Manual request (~7-10 business days).

How to Register as a The United Illuminating Company API Vendor

  1. 01For automated access, establish supplier/aggregator status and EDI with UI
  2. 02Use the Supplier Management System for lists, load profiles, and settlement
  3. 03For one-off customer data, submit Customer Data / Historical Usage Requests
  4. 04Consider Nectar for API-based multi-utility bill data (docs.nectarclimate.com)

05

EDI (Electronic Data Interchange)

Supported The United Illuminating Company EDI Transaction Sets

CodeNamePurpose
814Enrollment / Change / Drop / MoveCustomer enrollment, changes, drops, and moves in the deregulated market.
810InvoiceBilling and invoice reconciliation between UI and suppliers.
867Historical Usage / Interval DataSubmission of historical and interval usage data.
997Functional AcknowledgmentAcknowledges receipt and syntax of EDI transactions.

How to Enroll in The United Illuminating Company EDI

  1. 01Email supplier.relations@uinet.com requesting EDI setup and the CT EBT guides (814, 810, 867)
  2. 02Review transaction guides and configure your EDI system (VAN, SFTP, or web portal)
  3. 03Complete the Electric Supplier (or Aggregator) Service Agreement with required documents
  4. 04Complete EDI testing of enrollment, invoice, and usage transactions (4-6 weeks typical)
  5. 05Receive production credentials and go live

06

Rate Schedules & Tariff Analysis

UI bills separate delivery (distribution) from supply (generation). Delivery rates are set by PURA in base rate cases (most recently Docket 24-10-04, effective Nov 1, 2025), while generation is either a competitive supplier rate or UI Standard Service, reset every six months as a no-markup pass-through. For C&I customers, time-of-use schedules (GST, LPT) reward shifting load off the noon-8pm weekday peak, and transmission-voltage service (GST-TRA, LPT-TRA) lowers delivery charges for the largest loads. Verified generation figures are published; specific delivery cents/kWh and demand charges are in the PURA tariff sheets.

The United Illuminating Company Rate Schedule List

ScheduleApplicability
Rate GS / GSTCommercial standard and time-of-use service
Rate GST-TRACommercial TOU at transmission voltage
Rate LPT / LPT-TRALarge power TOU, distribution and transmission voltage
Rate GS-EVSE / GST-EVSECommercial EV charging stations

The United Illuminating Company Rate Features & TOU Details

  • Split delivery vs supply billing
  • Standard Service generation reset every Jan 1 and Jul 1
  • Time-of-use peak window: weekdays noon-8pm
  • Transmission-voltage schedules (GST-TRA, LPT-TRA) for the largest loads
  • Competitive supplier shopping available via EnergizeCT
  • Last Resort Service for LPT/GST customers over 500 kW

For a deeper analysis including cost optimization strategies and historical rate trends:

Read the full The United Illuminating Company Rate Optimization Guide →

07

Other Data Access Programs

Historical Usage Request Service

Structured process letting suppliers, aggregators, and authorized consultants request historical monthly billing and usage (kWh, kW, load profile) for customers with authorization.

  1. 01Establish supplier/aggregator status or obtain customer LOA
  2. 02Submit a Historical Usage Request to supplier.relations@uinet.com
  3. 03Specify customers, date ranges, and data types
  4. 04Receive CSV/Excel exports (5-10 business days, batches 7-15)

Supplier Management System (SMS)

Secure self-service portal for suppliers/aggregators offering customer non-confidential lists, load profiles, meter schedules, capacity, and settlement reports.

  1. 01Request SMS credentials from supplier.relations@uinet.com
  2. 02Log in to the SMS portal
  3. 03Download lists, load profiles, and settlement data
  4. 04Generate reports on the customer base

EV Managed Charging (Bidgely partnership)

Connecticut EV Managed Charging Program where enrolled customers share hourly consumption data with Bidgely for optimized charging.

  1. 01Enroll in the Connecticut EV charging program
  2. 02Consent to share hourly usage data with Bidgely
  3. 03Receive charging optimization recommendations

08

Limitations & Considerations

  • No Green Button Download or Connect My Data (peer Eversource has it)
  • No OAuth-based Share My Data third-party portal
  • No public developer API (REST/GraphQL)
  • Interval data requires a signed manual request, not self-service
  • EPA Portfolio Manager auto-upload not integrated
  • Most third-party access requires 5-10 business day manual turnarounds

09

The United Illuminating Company Data Access FAQ

How does a C&I customer get 15-minute interval data from UI?

UI has AMI meters capable of 15-minute reads, but interval data is not self-service. Submit a signed Interval Data Request Service Agreement to supplier.relations@uinet.com specifying account, meter, date range, and format. Data is delivered as CSV/Excel in roughly 7-10 business days, provided 'as is' and not guaranteed to match billing reads.

Does UI support EDI for suppliers and aggregators?

Yes. UI fully supports ANSI X12 / NAESB Connecticut EBT transactions including 814 (enrollment/change/drop/move), 810 (invoice), 867 (historical/interval usage), and 997 (acknowledgment). Setup runs through supplier.relations@uinet.com with a service agreement and testing phase (typically 4-6 weeks), via VAN, SFTP, or web portal.

Does UI offer Green Button or a public API?

No. UI has not implemented Green Button Download or Connect My Data, and offers no public REST/GraphQL API. Programmatic access is through EDI and the Supplier Management System for suppliers/aggregators, plus manual Customer Data and Historical Usage Requests. Nectar can also provide customer-authorized API access to UI data — see docs.nectarclimate.com.

Can a C&I customer shop for a competitive electricity supplier?

Yes. Connecticut is deregulated, so UI customers can buy generation from a licensed competitive supplier or take UI Standard Service (a no-markup pass-through reset every January 1 and July 1). UI always provides delivery. Compare supplier offers at EnergizeCT (Connecticut's official rate board).

Which rate schedules apply to commercial and industrial customers?

Commercial/industrial delivery service is billed under PURA-approved schedules effective November 1, 2025: Rate GS (General Service), Rate GST (General Service Time-of-Use), GST-TRA (transmission voltage), Rate LPT (Large Power Time-of-Use), LPT-TRA (transmission voltage), plus EV charging rates GS-EVSE and GST-EVSE. Standard Service generation rates are set separately every six months.

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