diff --git a/Sources/tart/Commands/Set.swift b/Sources/tart/Commands/Set.swift
index 39025f8..389c6d5 100644
--- a/Sources/tart/Commands/Set.swift
+++ b/Sources/tart/Commands/Set.swift
@@ -67,7 +67,9 @@ struct Set: AsyncParsableCommand {
       vmConfig.display.unit = display.unit
     }
 
-    vmConfig.displayRefit = displayRefit
+    if let displayRefit = displayRefit {
+      vmConfig.displayRefit = displayRefit
+    }
 
     if randomMAC {
       vmConfig.macAddress = VZMACAddress.randomLocallyAdministered()
diff --git a/Tests/TartTests/CommandBehaviorTests.swift b/Tests/TartTests/CommandBehaviorTests.swift
index a07750f..7194c00 100644
--- a/Tests/TartTests/CommandBehaviorTests.swift
+++ b/Tests/TartTests/CommandBehaviorTests.swift
@@ -206,6 +206,22 @@ final class CommandBehaviorTests: XCTestCase {
     }
   }
 
+  func testSetPreservesDisplayRefitWhenChangingOtherOptions() async throws {
+    try await withTemporaryTartHome {
+      let vmDir = try makeStandaloneVM(named: "display-refit", diskContents: "disk")
+      var vmConfig = try VMConfig(fromURL: vmDir.configURL)
+      vmConfig.displayRefit = false
+      try vmConfig.save(toURL: vmDir.configURL)
+
+      let command = try Set.parseAsRoot(["display-refit", "--cpu", "4"]) as! Set
+      try await command.run()
+
+      let updatedConfig = try VMConfig(fromURL: vmDir.configURL)
+      XCTAssertEqual(updatedConfig.displayRefit, false)
+      XCTAssertEqual(updatedConfig.cpuCount, 4)
+    }
+  }
+
   func testRemoteAdditionalDiskRetainsTemporaryBackingFileLock() throws {
     try withTemporaryTartHome {
       let storage = try VMStorageOCI()