diff --git a/crates/uv-workspace/src/pyproject_mut.rs b/crates/uv-workspace/src/pyproject_mut.rs
index 67b3f9ae3b61..d87a0343da3a 100644
--- a/crates/uv-workspace/src/pyproject_mut.rs
+++ b/crates/uv-workspace/src/pyproject_mut.rs
@@ -131,6 +131,7 @@ impl PyProjectTomlMut {
         };
         Ok(doc)
     }
+
     /// Adds a dependency to `project.dependencies`.
     ///
     /// Returns `true` if the dependency was added, `false` if it was updated.
@@ -431,7 +432,11 @@ impl PyProjectTomlMut {
             .as_table_mut()
             .ok_or(Error::MalformedSources)?;
 
+        if let Some(key) = find_source(name, sources) {
+            sources.remove(&key);
+        }
         add_source(name, source, sources)?;
+
         Ok(())
     }
 
@@ -532,7 +537,9 @@ impl PyProjectTomlMut {
             .map(|sources| sources.as_table_mut().ok_or(Error::MalformedSources))
             .transpose()?
         {
-            sources.remove(name.as_ref());
+            if let Some(key) = find_source(name, sources) {
+                sources.remove(&key);
+            }
         }
 
         Ok(())
@@ -766,6 +773,16 @@ fn find_dependencies(
     to_replace
 }
 
+/// Returns the key in `tool.uv.sources` that matches the given package name.
+fn find_source(name: &PackageName, sources: &Table) -> Option<String> {
+    for (key, _) in sources {
+        if PackageName::from_str(key).is_ok_and(|ref key| key == name) {
+            return Some(key.to_string());
+        }
+    }
+    None
+}
+
 // Add a source to `tool.uv.sources`.
 fn add_source(req: &PackageName, source: &Source, sources: &mut Table) -> Result<(), Error> {
     // Serialize as an inline table.
diff --git a/crates/uv/tests/it/edit.rs b/crates/uv/tests/it/edit.rs
index 33fc185f3cb9..080659d6973e 100644
--- a/crates/uv/tests/it/edit.rs
+++ b/crates/uv/tests/it/edit.rs
@@ -2717,6 +2717,175 @@ fn update_source_replace_url() -> Result<()> {
         );
     });
 
+    // Change the source again. The existing source should be replaced.
+    uv_snapshot!(context.filters(), context.add().arg("requests @ git+https://github.com/psf/requests").arg("--tag=v2.32.2"), @r###"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+
+    ----- stderr -----
+    Resolved 6 packages in [TIME]
+    Prepared 2 packages in [TIME]
+    Uninstalled 2 packages in [TIME]
+    Installed 2 packages in [TIME]
+     ~ project==0.1.0 (from file://[TEMP_DIR]/)
+     - requests==2.32.3 (from git+https://github.com/psf/requests@0e322af87745eff34caffe4df68456ebc20d9068)
+     + requests==2.32.2 (from git+https://github.com/psf/requests@88dce9d854797c05d0ff296b70e0430535ef8aaf)
+    "###);
+
+    let pyproject_toml = context.read("pyproject.toml");
+
+    insta::with_settings!({
+        filters => context.filters(),
+    }, {
+        assert_snapshot!(
+            pyproject_toml, @r###"
+        [project]
+        name = "project"
+        version = "0.1.0"
+        requires-python = ">=3.12"
+        dependencies = [
+            "requests[security]",
+        ]
+
+        [build-system]
+        requires = ["setuptools>=42"]
+        build-backend = "setuptools.build_meta"
+
+        [tool.uv.sources]
+        requests = { git = "https://github.com/psf/requests", tag = "v2.32.2" }
+        "###
+        );
+    });
+
+    Ok(())
+}
+
+/// If a source defined in `tool.uv.sources` but its name is not normalized, `uv add` should not
+/// add the same source again.
+#[test]
+#[cfg(feature = "git")]
+fn add_non_normalized_source() -> Result<()> {
+    let context = TestContext::new("3.12");
+
+    let pyproject_toml = context.temp_dir.child("pyproject.toml");
+    pyproject_toml.write_str(indoc! {r#"
+        [project]
+        name = "project"
+        version = "0.1.0"
+        requires-python = ">=3.12"
+        dependencies = [
+            "uv-public-pypackage"
+        ]
+
+        [build-system]
+        requires = ["setuptools>=42"]
+        build-backend = "setuptools.build_meta"
+
+        [tool.uv.sources]
+        uv_public_pypackage = { git = "https://github.com/astral-test/uv-public-pypackage", tag = "0.0.1" }
+        "#})?;
+
+    uv_snapshot!(context.filters(), context.add().arg("uv-public-pypackage @ git+https://github.com/astral-test/uv-public-pypackage@0.0.1"), @r###"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+
+    ----- stderr -----
+    Resolved 2 packages in [TIME]
+    Prepared 2 packages in [TIME]
+    Installed 2 packages in [TIME]
+     + project==0.1.0 (from file://[TEMP_DIR]/)
+     + uv-public-pypackage==0.1.0 (from git+https://github.com/astral-test/uv-public-pypackage@0dacfd662c64cb4ceb16e6cf65a157a8b715b979)
+    "###);
+
+    let pyproject_toml = context.read("pyproject.toml");
+
+    insta::with_settings!({
+        filters => context.filters(),
+    }, {
+        assert_snapshot!(
+            pyproject_toml, @r###"
+        [project]
+        name = "project"
+        version = "0.1.0"
+        requires-python = ">=3.12"
+        dependencies = [
+            "uv-public-pypackage",
+        ]
+
+        [build-system]
+        requires = ["setuptools>=42"]
+        build-backend = "setuptools.build_meta"
+
+        [tool.uv.sources]
+        uv-public-pypackage = { git = "https://github.com/astral-test/uv-public-pypackage", rev = "0.0.1" }
+        "###
+        );
+    });
+
+    Ok(())
+}
+
+/// If a source defined in `tool.uv.sources` but its name is not normalized, `uv remove` should
+/// remove the source.
+#[test]
+#[cfg(feature = "git")]
+fn remove_non_normalized_source() -> Result<()> {
+    let context = TestContext::new("3.12");
+
+    let pyproject_toml = context.temp_dir.child("pyproject.toml");
+    pyproject_toml.write_str(indoc! {r#"
+        [project]
+        name = "project"
+        version = "0.1.0"
+        requires-python = ">=3.12"
+        dependencies = [
+            "uv-public-pypackage"
+        ]
+
+        [build-system]
+        requires = ["setuptools>=42"]
+        build-backend = "setuptools.build_meta"
+
+        [tool.uv.sources]
+        uv_public_pypackage = { git = "https://github.com/astral-test/uv-public-pypackage", tag = "0.0.1" }
+        "#})?;
+
+    uv_snapshot!(context.filters(), context.remove().arg("uv-public-pypackage"), @r###"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+
+    ----- stderr -----
+    Resolved 1 package in [TIME]
+    Prepared 1 package in [TIME]
+    Installed 1 package in [TIME]
+     + project==0.1.0 (from file://[TEMP_DIR]/)
+    "###);
+
+    let pyproject_toml = context.read("pyproject.toml");
+
+    insta::with_settings!({
+        filters => context.filters(),
+    }, {
+        assert_snapshot!(
+            pyproject_toml, @r###"
+        [project]
+        name = "project"
+        version = "0.1.0"
+        requires-python = ">=3.12"
+        dependencies = []
+
+        [build-system]
+        requires = ["setuptools>=42"]
+        build-backend = "setuptools.build_meta"
+
+        [tool.uv.sources]
+        "###
+        );
+    });
+
     Ok(())
 }