diff --git a/src/dawn_native/Buffer.cpp b/src/dawn_native/Buffer.cpp
index 6e4415c908..10673207a6 100644
--- a/src/dawn_native/Buffer.cpp
+++ b/src/dawn_native/Buffer.cpp
@@ -329,17 +329,6 @@ namespace dawn_native {
         // Handle the defaulting of size required by WebGPU, even if in webgpu_cpp.h it is not
         // possible to default the function argument (because there is the callback later in the
         // argument list)
-        if (size == 0) {
-            // Using 0 to indicating default size is deprecated.
-            // Temporarily treat 0 as undefined for size, and give a warning
-            // TODO(dawn:1058): Remove this if block
-            size = wgpu::kWholeMapSize;
-            GetDevice()->EmitDeprecationWarning(
-                "Using size=0 to indicate default mapping size for mapAsync "
-                "is deprecated. In the future it will result in a zero-size mapping. "
-                "Use `undefined` (wgpu::kWholeMapSize) or just omit the parameter instead.");
-        }
-
         if ((size == wgpu::kWholeMapSize) && (offset <= mSize)) {
             size = mSize - offset;
         }
diff --git a/src/tests/end2end/DeprecatedAPITests.cpp b/src/tests/end2end/DeprecatedAPITests.cpp
index 097185ed54..68beae9f38 100644
--- a/src/tests/end2end/DeprecatedAPITests.cpp
+++ b/src/tests/end2end/DeprecatedAPITests.cpp
@@ -71,32 +71,6 @@ TEST_P(DeprecationTests, SetBufferWithZeroSizeAsDefault) {
     }
 }
 
-// Test that using size=0 to indicate default size in mapAsync of buffer is
-// deprecated.
-TEST_P(DeprecationTests, BufferMapAsyncWithZeroSizeAsDefault) {
-    wgpu::BufferDescriptor bufferDesc;
-    bufferDesc.size = 128;
-    bufferDesc.usage = wgpu::BufferUsage::MapWrite;
-
-    {
-        // Control case, use wgpu::kWholeMapSize to indicate default size.
-        wgpu::Buffer buffer = device.CreateBuffer(&bufferDesc);
-
-        buffer.MapAsync(wgpu::MapMode::Write, 0, wgpu::kWholeMapSize, nullptr, nullptr);
-
-        WaitForAllOperations();
-    }
-
-    {
-        // Deprecated case, use 0 to indicate default size will cause deprecated warning.
-        wgpu::Buffer buffer = device.CreateBuffer(&bufferDesc);
-
-        EXPECT_DEPRECATION_WARNING(buffer.MapAsync(wgpu::MapMode::Write, 0, 0, nullptr, nullptr));
-
-        WaitForAllOperations();
-    }
-}
-
 DAWN_INSTANTIATE_TEST(DeprecationTests,
                       D3D12Backend(),
                       MetalBackend(),
diff --git a/src/tests/unittests/validation/BufferValidationTests.cpp b/src/tests/unittests/validation/BufferValidationTests.cpp
index ff5b00afc9..7651b90978 100644
--- a/src/tests/unittests/validation/BufferValidationTests.cpp
+++ b/src/tests/unittests/validation/BufferValidationTests.cpp
@@ -219,21 +219,13 @@ TEST_F(BufferValidationTest, MapAsync_OffsetSizeOOB) {
     // Valid case: empty range at the end of the buffer is ok.
     {
         wgpu::Buffer buffer = CreateMapReadBuffer(8);
-        // Currently using size=0 will cause a deprecation warning, and result in default size.
-        // After the deprecation is finished, size=0 will result in a mapping with zero size
-        // exactly.
-        // TODO(dawn:1058): Remove the deprecation warning expection after the removal.
-        EXPECT_DEPRECATION_WARNING(buffer.MapAsync(wgpu::MapMode::Read, 8, 0, nullptr, nullptr));
+        buffer.MapAsync(wgpu::MapMode::Read, 8, 0, nullptr, nullptr);
     }
 
     // Error case, offset is larger than the buffer size (even if size is 0).
     {
         wgpu::Buffer buffer = CreateMapReadBuffer(12);
-        // Currently using size=0 will cause a deprecation warning, and result in default size.
-        // After the deprecation is finished, size=0 will result in a mapping with zero size
-        // exactly.
-        // TODO(dawn:1058): Remove the deprecation warning expection after the removal.
-        EXPECT_DEPRECATION_WARNING(AssertMapAsyncError(buffer, wgpu::MapMode::Read, 16, 0));
+        AssertMapAsyncError(buffer, wgpu::MapMode::Read, 16, 0);
     }
 
     // Error case, offset + size is larger than the buffer