Connecticut Light & Power (Eversource CT) Data Access Guide
The Connecticut Light and Power Company, doing business as Eversource Energy, delivers electricity to roughly 1.29 million customers across Connecticut. CT is a deregulated electric market: Eversource owns the wires and bills delivery, while customers can buy generation from competitive suppliers or take Standard Service at a regulated Rate to Compare.
How to Get Your Connecticut Light & Power (Eversource CT) Data: All Access Methods
| Method | 1st Party | 3rd Party | Customer Types | Data Types | Latency | Format |
|---|---|---|---|---|---|---|
| Online Billing Portal | ✓ | — | Residential & C&I | Bills, payments, usage summary | Real-time / monthly | HTML, PDF |
| Energy Profiler Online (EPO) | ✓ | ✓ | C&I with interval meters | Interval usage | Daily (phone-accessed meters) | Web portal, CSV |
| Green Button Download My Data | ✓ | — | All customers | 13 months usage | On demand | XML (ESPI) |
| Green Button Connect My Data / UtilityAPI | — | ✓ | All customers (via OAuth) | Usage, interval, billing | 5-15 min after auth | JSON, XML (ESPI) |
| ENERGY STAR Portfolio Manager | ✓ | ✓ | C&I / building owners | Monthly building energy | Monthly | ESPM format |
| Energy Reporting & Disclosure Portal | ✓ | ✓ | Building owners/managers | Aggregate building usage | Monthly | Excel, PDF |
Billing Data Access
Eversource offers C&I customers a self-service online account portal with up to 36 months of billing history. Bills are viewable in HTML and can be saved as PDF; no native CSV/XML billing export is documented. Automated monthly billing data can flow to ENERGY STAR Portfolio Manager via a direct utility data connection.
What Data Is on Your Connecticut Light & Power (Eversource CT) Bill
- Current bill amount and due date
- Payment history
- Up to 36 months of prior bills
- Energy usage summary
- Delivery vs. supply cost breakdown
- Rate information
- Peak demand (kW) where applicable via Portfolio Manager
How to Download Connecticut Light & Power (Eversource CT) Bills (Business & Commercial)
- 01Create or log in to the Eversource business online account
- 02Open Past Bills and Payments for billing history (up to 36 months)
- 03For automated benchmarking, create an ENERGY STAR Portfolio Manager account and add the building/meters
- 04In Portfolio Manager, select Eversource and choose Direct Utility Data Connection
- 05Authorize data sharing; monthly billing data flows automatically 1-2 business days after each billing period closes
How to Download Connecticut Light & Power (Eversource CT) Bills (Residential)
- 01Create an online account at eversource.com/security/account/login
- 02Verify email
- 03Log in and open Past Bills and Payments
- 04View or print up to 36 months of bills
Third-Party Access to Connecticut Light & Power (Eversource CT) Billing Data
ENERGY STAR Portfolio Manager (consultant access)
- 01Building owner creates a Portfolio Manager account and connects to Eversource
- 02Owner invites the consultant/energy manager as a connected user
- 03Consultant accepts and is granted view or full access to specified buildings
- 04Monthly billing data syncs automatically
Energy Reporting & Disclosure Portal
- 01Owner registers and verifies building ownership with EnergyDisclosure@eversource.com
- 02Owner adds property and Eversource account numbers
- 03For multi-tenant buildings, owner collects signed tenant authorization forms
- 04Owner adds third-party user; aggregate building usage becomes available
Want to understand the charges on your bill?
See the Connecticut Light & Power (Eversource CT) Rate Schedules & Tariff Guide →Interval Data & Smart Meters
Interval meter data for C&I accounts with interval-recording meters is delivered through Energy Profiler Online (EPO), a Schneider Electric-hosted portal. Eversource is also deploying Advanced Metering Infrastructure (AMI) across Connecticut, which will add near-real-time interval data via web, app, and (expected) Green Button.
How to Download Connecticut Light & Power (Eversource CT) Interval Data via Green Button
- 01Log in to your Eversource account
- 02Navigate to the Green Button section in savings tools or account area
- 03Click the Green Button icon and review the authorization
- 04Confirm and download 13 months of usage as ESPI (NAESB REQ.21) XML
- 05Open with Green Button-compatible analysis software
Interval data is essential for rate comparison and TOU analysis.
See which Connecticut Light & Power (Eversource CT) rate schedule is best for your usage pattern →Third-Party API Access
Eversource exposes third-party programmatic access primarily through a UtilityAPI-powered gateway (usagelink.eversource.com) using Green Button OAuth. Third parties register, start in sandbox mode, then request live access; each customer must authorize via OAuth. Documented today for Eversource Massachusetts with a comparable Connecticut process.
Available Connecticut Light & Power (Eversource CT) API Endpoints
| Function | Endpoint | Method | Format |
|---|---|---|---|
| Retrieve authorized usage | UtilityAPI / Green Button ESPI endpoint | GET | JSON / XML (ESPI) |
How to Register as a Connecticut Light & Power (Eversource CT) API Vendor
- 01Register as a third-party provider at the UtilityAPI/Eversource gateway
- 02Develop and test integration in sandbox mode against test accounts
- 03Request live-mode approval from Eversource/UtilityAPI
- 04Send each customer a Green Button OAuth authorization request
- 05Receive an access token and retrieve data via REST API (JSON)
EDI (Electronic Data Interchange)
Supported Connecticut Light & Power (Eversource CT) EDI Transaction Sets
| Code | Name | Purpose |
|---|---|---|
| 810 | Invoice | Billing/invoice between Eversource and suppliers |
| 814 | Enrollment / Change Request | Supplier enrollment and account change requests |
| 867 | Historical Usage | Usage data exchange to suppliers |
How to Enroll in Connecticut Light & Power (Eversource CT) EDI
- 01EDI is oriented to licensed electric suppliers, not direct C&I data retrieval
- 02Suppliers establish EBT/EDI connectivity per Eversource EBT guides
- 03Transactions exchanged via VAN or direct connection
- 04For C&I customer data, use EPO, Green Button, Portfolio Manager, or the disclosure portal instead
Sources
Rate Schedules & Tariff Analysis
Eversource CT separates regulated delivery from competitive supply. The Standard Service generation price (Rate to Compare) is the key lever for C&I customers and resets twice yearly; the Jan 1, 2026 small-C&I rate of 10.710 cents/kWh (up ~23%) makes supplier shopping and demand management financially material. Demand-metered classes (55-58) add per-kW demand charges, so load-factor improvement and peak shaving drive savings.
Connecticut Light & Power (Eversource CT) Rate Schedule List
| Schedule | Applicability |
|---|---|
| Rate 30 / 35 | Small commercial & industrial |
| Rate 55 / 56 | Medium manufacturing / non-manufacturing |
| Rate 57 / 58 | Large manufacturing / non-manufacturing |
| Variable Peak Pricing | >=500 kW demand accounts |
Connecticut Light & Power (Eversource CT) Rate Features & TOU Details
- Deregulated supply with semi-annual Standard Service resets (Jan 1 / Jul 1)
- Demand ($/kW) charges for medium and large classes
- Variable Peak Pricing option for >=500 kW accounts
- Delivery rates reviewed semi-annually by PURA
For a deeper analysis including cost optimization strategies and historical rate trends:
Read the full Connecticut Light & Power (Eversource CT) Rate Optimization Guide →Other Data Access Programs
Energy Reporting & Disclosure Portal
Provides aggregate building-level electric and gas usage to support Connecticut benchmarking statutes (CGS 16a-37t, 16-245ii) and ENERGY STAR benchmarking.
- 01Register and verify building ownership
- 02Add property and Eversource account numbers
- 03Collect tenant authorizations for multi-tenant buildings
- 04View/download aggregate usage in Excel/PDF
ENERGY STAR Portfolio Manager Integration
Automated monthly transfer of building energy data via a direct utility data connection for benchmarking.
- 01Create a Portfolio Manager account and building profile
- 02Select Eversource and Direct Utility Data Connection
- 03Authorize data sharing
- 04Receive automatic monthly updates
Property Management Gateway (CT)
Portal for multi-property owners/managers to manage service across locations (limited usage analytics).
- 01Log in to the landlord/property portal
- 02Manage service and disconnection authorizations
- 03Monitor service status across properties
Limitations & Considerations
- ⚠No native CSV or XML export for billing data in the standard portal (HTML/PDF only).
- ⚠EPO interval data carries per-account fees ($50 one-time / $25 month / $300 year) and is informational, not billing-quality.
- ⚠AMI deployment is in progress; standardized 15-minute interval access and Green Button via smart meters are not yet universal.
- ⚠Green Button Connect My Data / UtilityAPI is fully documented for Eversource Massachusetts; the Connecticut process is comparable but evolving.
- ⚠Accounts with multi-factor authentication require a short re-authorization step for OAuth-based third-party access.
Connecticut Light & Power (Eversource CT) Data Access FAQ
How does a Connecticut business get interval (15-minute) usage data from Eversource?▾
C&I accounts with interval-recording meters enroll in Energy Profiler Online (EPO) by submitting a signed Service Agreement to EPOAdmin@eversource.com or 866-658-2356. Pricing is $50 for a one-time request, $25/month, or $300/year per account. As AMI smart meters roll out statewide, interval data will increasingly be available through the online portal and Green Button without an EPO subscription.
Can a third-party energy manager pull our data automatically?▾
Yes. The cleanest automated path is Green Button Connect My Data through Eversource's UtilityAPI gateway (usagelink.eversource.com), where you authorize the vendor via an OAuth flow. For benchmarking, you can also grant access through ENERGY STAR Portfolio Manager or the Energy Reporting & Disclosure Portal. EPO also accepts a signed Service Agreement as a Letter of Authorization for brokers and aggregators.
What is the Rate to Compare and why does it matter for our facility?▾
Connecticut is deregulated, so your bill splits into delivery (set by Eversource/PURA) and supply (generation). Standard Service is the default supply price, also called the Rate to Compare. For small C&I (Rate 30 and 35) it reset to 10.710 cents/kWh effective January 1, 2026 and changes again July 1. If a competitive supplier offers a fixed price below the Rate to Compare for your usage profile, switching supply can lower the energy portion of your bill without changing delivery service.
Which Eversource CT rate class applies to our business?▾
Most small businesses are on Rate 30 or Rate 35. Larger facilities fall into Rate 55 (medium manufacturing), Rate 56 (medium non-manufacturing), Rate 57 (large manufacturing), or Rate 58 (large non-manufacturing). Rate 27 is a small-business time-of-use option. Variable Peak Pricing is available for accounts with maximum demand of 500 kW or greater. Exact charges are in the Eversource CT electric tariff.
Does Eversource offer Green Button download in Connecticut?▾
Yes. Any Eversource customer can download up to 13 months of electricity usage in standardized ESPI (NAESB REQ.21) XML from the Green Button section of their online account, suitable for import into energy analysis software.
The Best Way to Access Data from Connecticut Light & Power (Eversource CT)
Nectar connects to Connecticut Light & Power (Eversource CT) and 7,000+ utility providers — billing, interval, and rate data delivered automatically. No portals, no forms, no manual downloads.
Nectar for Energy & Sustainability Teams
Managing utility data for commercial or industrial buildings? Nectar offers a free energy data audit — we'll review your current setup and show you where automation can save your team hours every month.
Get a Free AuditNectar for Developers & Consultants
Building energy tools or advising clients on utility data? Nectar works with technology partners and consultants who need reliable data infrastructure.
Partner with Us