diff --git a/.coveragerc b/.coveragerc
new file mode 100644
index 0000000..71c0278
--- /dev/null
+++ b/.coveragerc
@@ -0,0 +1,37 @@
+# .coveragerc to control coverage.py
+[run]
+branch = False
+source = dqmc
+
+[report]
+exclude_lines =
+    # Have to re-enable the standard pragma
+    pragma: no cover
+
+	# Don't complain about debug-only code and print statements:
+    def __repr__
+    def __str__
+
+	# Don't complain about abstract methods
+    @abstract
+    @njit
+
+    # Don't complain if tests don't hit defensive assertion code:
+    raise AssertionError
+    raise NotImplementedError
+
+    # Don't complain if non-runnable code isn't run:
+    if 0:
+    if __name__ == .__main__.:
+
+ignore_errors = True
+
+# Skip source files:
+omit =
+  dqmc/tests/*
+  dqmc/__init__.py
+  dqmc/__main__.py
+  dqmc/mfuncs.py
+  dqmc/data.py
+  dqmc/logging.py
+  dqmc/_version.py
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index c8cb49e..7f99dab 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -41,11 +41,18 @@ jobs:
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip
-        pip install pytest
-        if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
+        pip install pytest pytest-cov codecov
+        pip install -r requirements.txt
     - name: Build Fortran source code
       run: |
         make
-    - name: Run all tests
+    - name: Run tests
       run: |
-        pytest dqmc/
+        pytest dqmc/ --cov=dqmc --cov-report=xml -v
+    - name: Upload coverage to Codecov
+      uses: codecov/codecov-action@v2
+      with:
+        env_vars: OS,PYTHON
+        verbose: True
+    - name: Coverage
+      run: codecov
diff --git a/README.md b/README.md
index 4c85287..f2f3bdc 100644
--- a/README.md
+++ b/README.md
@@ -3,10 +3,10 @@
 ![GitHub tag (latest by date)](https://img.shields.io/github/v/tag/dylanljones/dqmc)
 ![GitHub license](https://img.shields.io/github/license/dylanljones/dqmc)
 
-|        |                                      |                                       |
-|:-------|:-------------------------------------|:--------------------------------------|
-| Master | [![Build][build-master]][build-link] | [![Tests][tests-master]][test-link]   |
-| Dev    | [![Build][build-dev]][build-link]    | [![Tests][tests-dev]][test-link]      |
+|        |                                      |                                       |                                                   |
+|:-------|:-------------------------------------|:--------------------------------------|:--------------------------------------------------|
+| Master | [![Build][build-master]][build-link] | [![Tests][tests-master]][test-link]   | [![Codecov][codecov-master]][codecov-master-link] |
+| Dev    | [![Build][build-dev]][build-link]    | [![Tests][tests-dev]][test-link]      | [![Codecov][codecov-dev]][codecov-dev-link]       |
 
 [build-master]: https://img.shields.io/github/workflow/status/dylanljones/dqmc/Build/master?label=build&logo=github&style=flat-square
 [build-dev]: https://img.shields.io/github/workflow/status/dylanljones/dqmc/Build/dev?label=build&logo=github&style=flat-square
@@ -16,6 +16,11 @@
 [tests-dev]: https://img.shields.io/github/workflow/status/dylanljones/dqmc/Tests/dev?label=tests&logo=github&style=flat-square
 [test-link]: https://github.com/dylanljones/dqmc/actions/workflows/test.yml
 
+[codecov-master]: https://img.shields.io/codecov/c/github/dylanljones/dqmc/master?logo=codecov&style=flat-square
+[codecov-master-link]: https://app.codecov.io/gh/dylanljones/dqmc/branch/master
+[codecov-dev]: https://img.shields.io/codecov/c/github/dylanljones/dqmc/dev?logo=codecov&style=flat-square
+[codecov-dev-link]: https://app.codecov.io/gh/dylanljones/dqmc/branch/dev
+
 Efficient and stable Determinant Quantum Monte Carlo (DQMC) simulations of the Hubbard model in Python.
 
 | :warning: **WARNING**: This project is still in development and might contain errors or change significantly in the future! |