diff --git a/crates/uv-distribution/src/metadata/lowering.rs b/crates/uv-distribution/src/metadata/lowering.rs
index 0e7cb1a5bbb3f..51fffa0c908a0 100644
--- a/crates/uv-distribution/src/metadata/lowering.rs
+++ b/crates/uv-distribution/src/metadata/lowering.rs
@@ -185,9 +185,6 @@ impl LoweredRequirement {
                             marker,
                             ..
                         } => {
-                            if matches!(requirement.version_or_url, Some(VersionOrUrl::Url(_))) {
-                                return Err(LoweringError::ConflictingUrls);
-                            }
                             let source = git_source(
                                 &git,
                                 subdirectory.map(PathBuf::from),
@@ -203,9 +200,6 @@ impl LoweredRequirement {
                             marker,
                             ..
                         } => {
-                            if matches!(requirement.version_or_url, Some(VersionOrUrl::Url(_))) {
-                                return Err(LoweringError::ConflictingUrls);
-                            }
                             let source = url_source(url, subdirectory.map(PathBuf::from))?;
                             (source, marker)
                         }
@@ -215,9 +209,6 @@ impl LoweredRequirement {
                             marker,
                             ..
                         } => {
-                            if matches!(requirement.version_or_url, Some(VersionOrUrl::Url(_))) {
-                                return Err(LoweringError::ConflictingUrls);
-                            }
                             let source = path_source(
                                 PathBuf::from(path),
                                 git_member,
@@ -276,9 +267,6 @@ impl LoweredRequirement {
                             if !is_workspace {
                                 return Err(LoweringError::WorkspaceFalse);
                             }
-                            if matches!(requirement.version_or_url, Some(VersionOrUrl::Url(_))) {
-                                return Err(LoweringError::ConflictingUrls);
-                            }
                             let member = workspace
                                 .packages()
                                 .get(&requirement.name)
@@ -433,9 +421,6 @@ impl LoweredRequirement {
                             marker,
                             ..
                         } => {
-                            if matches!(requirement.version_or_url, Some(VersionOrUrl::Url(_))) {
-                                return Err(LoweringError::ConflictingUrls);
-                            }
                             let source = git_source(
                                 &git,
                                 subdirectory.map(PathBuf::from),
@@ -451,9 +436,6 @@ impl LoweredRequirement {
                             marker,
                             ..
                         } => {
-                            if matches!(requirement.version_or_url, Some(VersionOrUrl::Url(_))) {
-                                return Err(LoweringError::ConflictingUrls);
-                            }
                             let source = url_source(url, subdirectory.map(PathBuf::from))?;
                             (source, marker)
                         }
@@ -463,9 +445,6 @@ impl LoweredRequirement {
                             marker,
                             ..
                         } => {
-                            if matches!(requirement.version_or_url, Some(VersionOrUrl::Url(_))) {
-                                return Err(LoweringError::ConflictingUrls);
-                            }
                             let source = path_source(
                                 PathBuf::from(path),
                                 None,
@@ -550,8 +529,6 @@ pub enum LoweringError {
     InvalidUrl(#[from] url::ParseError),
     #[error(transparent)]
     InvalidVerbatimUrl(#[from] uv_pep508::VerbatimUrlError),
-    #[error("Can't combine URLs from both `project.dependencies` and `tool.uv.sources`")]
-    ConflictingUrls,
     #[error("Fragments are not allowed in URLs: `{0}`")]
     ForbiddenFragment(Url),
     #[error("`workspace = false` is not yet supported")]
@@ -678,7 +655,19 @@ fn registry_source(
             index: Some(index),
             conflict,
         }),
-        Some(VersionOrUrl::Url(_)) => Err(LoweringError::ConflictingUrls),
+        Some(VersionOrUrl::Url(_)) => {
+            if matches!(bounds, LowerBound::Warn) {
+                warn_user_once!(
+                    "Missing version constraint (e.g., a lower bound) for `{}`",
+                    requirement.name
+                );
+            }
+            Ok(RequirementSource::Registry {
+                specifier: VersionSpecifiers::empty(),
+                index: Some(index),
+                conflict,
+            })
+        }
     }
 }
 
diff --git a/crates/uv-distribution/src/metadata/requires_dist.rs b/crates/uv-distribution/src/metadata/requires_dist.rs
index 0c33dfd12e6b3..6a71201f61f8e 100644
--- a/crates/uv-distribution/src/metadata/requires_dist.rs
+++ b/crates/uv-distribution/src/metadata/requires_dist.rs
@@ -568,7 +568,7 @@ mod test {
 
         assert_snapshot!(format_err(input).await, @r###"
         error: Failed to parse entry: `tqdm`
-          Caused by: Can't combine URLs from both `project.dependencies` and `tool.uv.sources`
+          Caused by: `tqdm` references a workspace in `tool.uv.sources` (e.g., `tqdm = { workspace = true }`), but is not a workspace member
         "###);
     }
 
diff --git a/crates/uv/tests/it/lock.rs b/crates/uv/tests/it/lock.rs
index 38c5e89007801..f0956f851ed4e 100644
--- a/crates/uv/tests/it/lock.rs
+++ b/crates/uv/tests/it/lock.rs
@@ -9738,7 +9738,7 @@ fn lock_transitive_extra() -> Result<()> {
 }
 
 /// If a source is provided via `tool.uv.sources` _and_ a URL is provided in `project.dependencies`,
-/// we raise an error.
+/// we accept the source in `tool.uv.sources`, unless `--no-sources` is provided.
 #[test]
 fn lock_mismatched_sources() -> Result<()> {
     let context = TestContext::new("3.12");
@@ -9760,16 +9760,88 @@ fn lock_mismatched_sources() -> Result<()> {
     )?;
 
     uv_snapshot!(context.filters(), context.lock(), @r###"
-    success: false
-    exit_code: 1
+    success: true
+    exit_code: 0
     ----- stdout -----
 
     ----- stderr -----
-      × Failed to build `project @ file://[TEMP_DIR]/`
-      ├─▶ Failed to parse entry: `uv-public-pypackage`
-      ╰─▶ Can't combine URLs from both `project.dependencies` and `tool.uv.sources`
+    Resolved 2 packages in [TIME]
     "###);
 
+    let lock = context.read("uv.lock");
+
+    insta::with_settings!({
+        filters => context.filters(),
+    }, {
+        assert_snapshot!(
+            lock, @r###"
+        version = 1
+        requires-python = ">=3.12"
+
+        [options]
+        exclude-newer = "2024-03-25T00:00:00Z"
+
+        [[package]]
+        name = "project"
+        version = "0.1.0"
+        source = { virtual = "." }
+        dependencies = [
+            { name = "uv-public-pypackage" },
+        ]
+
+        [package.metadata]
+        requires-dist = [{ name = "uv-public-pypackage", git = "https://github.com/astral-test/uv-public-pypackage?tag=0.0.1" }]
+
+        [[package]]
+        name = "uv-public-pypackage"
+        version = "0.1.0"
+        source = { git = "https://github.com/astral-test/uv-public-pypackage?tag=0.0.1#0dacfd662c64cb4ceb16e6cf65a157a8b715b979" }
+        "###
+        );
+    });
+
+    // If we run with `--no-sources`, we should use the URL provided in `project.dependencies`.
+    uv_snapshot!(context.filters(), context.lock().arg("--no-sources"), @r###"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+
+    ----- stderr -----
+    Resolved 2 packages in [TIME]
+    "###);
+
+    let lock = context.read("uv.lock");
+
+    insta::with_settings!({
+        filters => context.filters(),
+    }, {
+        assert_snapshot!(
+            lock, @r###"
+        version = 1
+        requires-python = ">=3.12"
+
+        [options]
+        exclude-newer = "2024-03-25T00:00:00Z"
+
+        [[package]]
+        name = "project"
+        version = "0.1.0"
+        source = { virtual = "." }
+        dependencies = [
+            { name = "uv-public-pypackage" },
+        ]
+
+        [package.metadata]
+        requires-dist = [{ name = "uv-public-pypackage", git = "https://github.com/astral-test/uv-public-pypackage?rev=0.0.2" }]
+
+        [[package]]
+        name = "uv-public-pypackage"
+        version = "0.1.0"
+        source = { git = "https://github.com/astral-test/uv-public-pypackage?rev=0.0.2#b270df1a2fb5d012294e9aaf05e7e0bab1e6a389" }
+        "###
+        );
+    });
+
     Ok(())
 }