Terraform Provider: plancost

The plancost provider allows you to estimate, track, and optimize cloud costs directly within your Terraform workflow. By integrating cost estimation as a native Terraform resource, you get cost visibility, policy enforcement, and security without leaving your infrastructure code.

Website: https://plancost.io

Overview

Unlike CLI wrappers, plancost works as a genuine Terraform Provider. This means cost data is stored in your state file, accessible to other resources, and verifiable by standard policy tools.

Prerequisites

• Terraform >= 1.11.x
• plancost provider installed (or configured via development overrides)

Quick Start

1. Setup

Install the plancost provider by adding it to your Terraform configuration.

terraform {
  required_providers {
    plancost = {
      source = "plancost/plancost"
    }
  }
}

resource "plancost_estimate" "this" {
  working_directory = abspath(path.module)
}

2. Run Terraform Plan

Execute terraform plan. You will see the plancost_estimate resource being created (or updated) and a formatted cost breakdown in the outputs.

terraform plan

Example Output:

Terraform will perform the following actions:

  # azurerm_public_ip.test will be created
  + resource "azurerm_public_ip" "test" {
      ...
    }

  # plancost_estimate.this will be created
  + resource "plancost_estimate" "this" {
      + monthly_cost = 3.65
      + resources    = {
          + "azurerm_public_ip.test" = {
              + cost_components = {
                  + "IP address (static, regional)" = {
                      + monthly_cost     = 3.65
                      + monthly_quantity = "730"
                      + unit             = "hours"
                    }
                }
              + sub_resources   = {}
            }
        }
      + view = <<-EOT
        Project: main
        
         Name                                                         Monthly Qty  Unit    Monthly Cost
        
         azurerm_public_ip.test
         └─ IP address (static, regional)                             730          hours   $3.65
        
         OVERALL TOTAL                                                                     $3.65
    EOT
    }

Plan: 3 to add, 0 to change, 0 to destroy.

3. Track Cost Changes

When you modify your infrastructure (e.g., changing a SKU), terraform plan will show the cost difference in the plancost_estimate resource and the output.

Example: Changing Public IP SKU from Standard to Basic

  # plancost_estimate.this will be updated in-place
  ~ resource "plancost_estimate" "this" {
      ~ monthly_cost = 3.65 -> 2.63
      ~ view = <<-EOT
        Project: main
        
         Name                                                         Monthly Qty  Unit    Monthly Cost
        
         azurerm_public_ip.test
      -  └─ IP address (static, regional)                             730          hours   $3.65
      +  └─ IP address (static, regional)                             730          hours   $2.63
        
      -  OVERALL TOTAL                                                                     $3.65
      +  OVERALL TOTAL                                                                     $2.63
    EOT
  }

Why plancost?

Feature	Others	plancost
Setup	Binary Install + Auth + CI Scripting	Copy-paste 6 lines of HCL. No Sign-up.
Workflow	Separate CLI command	Native terraform plan integration
Diff View	Multi-step process / External Dashboard	Inline in terraform plan output
Cost Guardrails	External Policies (OPA/Sentinel)	Defined in HCL (Native Resource)
Tagging Policies	External Dashboards	Defined in HCL (Native Resource)
Platform Support	Custom hooks for Atlantis/TFC	Works out-of-the-box everywhere
Policy Engines	Requires custom input parsing	Native HCL Resource
CI/CD	Requires CLI Installation	Zero-Install (Standard terraform init)
State	Locked in SaaS Dashboard	Stored in terraform.tfstate
Privacy	Sends Configs, Names & Paths to SaaS	Anonymous (SKU/Region only)

Supported Providers

Currently, plancost focuses on Microsoft Azure, providing deep coverage for the top 100+ most common resources (matching and exceeding other tools).

For a complete list of supported resources and their pricing status, see the Supported Resources guide.

• Azure: ✅ Full Support (500+ resources)
• AWS: 🚧 Planned
• GCP: 🚧 Planned

Examples

Explore our examples directory for complete use cases:

• Quickstart: Basic usage with Azure Public IP.
• Cost Guardrails: Enforce budget limits and cost increase policies.
• Tagging Policies: Validate required tags and allowed values.
• Usage Estimation: Improve accuracy with usage files (also see Inline Usage and Wildcards).
• CI/CD Integration: GitHub Actions workflow example.
• Pull Request Comments: Export estimates for PR comments.
• Policy as Code (OPA): Advanced policies using Rego.
• Cost Optimization: Get recommendations for cost savings.
• Simple Discounting: Apply negotiated discounts to estimates.
• Variables: Working with Terraform variables and .tfvars files.

Credits

This project uses source code from Infracost. We would like to thank the Infracost team for their amazing work in the cloud cost estimation space.

Contributing

By submitting a Pull Request, you agree that your contributions are licensed under the Mozilla Public License 2.0.

License

This project is licensed under the Mozilla Public License 2.0 (MPL-2.0).

See the LICENSE file for specific terms and conditions.

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This project also includes code from Infracost, which is licensed under the Apache License 2.0. See LICENSE_INFRACOST and NOTICE for details.