diff --git a/include/verilated.cpp b/include/verilated.cpp
index a4968ccd7..fd80ae41a 100644
--- a/include/verilated.cpp
+++ b/include/verilated.cpp
@@ -2650,7 +2650,7 @@ const char* VerilatedContext::timeprecisionString() const VL_MT_SAFE {
 }
 
 void VerilatedContext::threads(unsigned n) {
-    if (n == 0) VL_FATAL_MT(__FILE__, __LINE__, "", "%Error: Simulation threads must be >= 1");
+    if (n == 0) VL_FATAL_MT(__FILE__, __LINE__, "", "Simulation threads must be >= 1");
 
     if (m_threadPool) {
         VL_FATAL_MT(
diff --git a/include/verilated_cov.cpp b/include/verilated_cov.cpp
index 412102476..6aa1ec5eb 100644
--- a/include/verilated_cov.cpp
+++ b/include/verilated_cov.cpp
@@ -233,7 +233,7 @@ private:
         // Little selftest
 #define SELF_CHECK(got, exp) \
     do { \
-        if ((got) != (exp)) VL_FATAL_MT(__FILE__, __LINE__, "", "%Error: selftest"); \
+        if ((got) != (exp)) VL_FATAL_MT(__FILE__, __LINE__, "", "selftest"); \
     } while (0)
         SELF_CHECK(combineHier("a.b.c", "a.b.c"), "a.b.c");
         SELF_CHECK(combineHier("a.b.c", "a.b"), "a.b*");
diff --git a/include/verilated_timing.cpp b/include/verilated_timing.cpp
index f7ceec357..0724a43e9 100644
--- a/include/verilated_timing.cpp
+++ b/include/verilated_timing.cpp
@@ -89,7 +89,7 @@ void VlDelayScheduler::resume() {
 uint64_t VlDelayScheduler::nextTimeSlot() const {
     if (!m_queue.empty()) return m_queue.cbegin()->first;
     if (m_zeroDelayed.empty())
-        VL_FATAL_MT(__FILE__, __LINE__, "", "%Error: There is no next time slot scheduled");
+        VL_FATAL_MT(__FILE__, __LINE__, "", "There is no next time slot scheduled");
     return m_context.time();
 }
 
diff --git a/src/V3EmitCModel.cpp b/src/V3EmitCModel.cpp
index 54f625d13..d31dc8ca6 100644
--- a/src/V3EmitCModel.cpp
+++ b/src/V3EmitCModel.cpp
@@ -473,8 +473,7 @@ class EmitCModel final : public EmitCFunc {
         } else {
             putns(modp, "bool " + topClassName() + "::eventsPending() { return false; }\n\n");
             puts("uint64_t " + topClassName() + "::nextTimeSlot() {\n");
-            puts("VL_FATAL_MT(__FILE__, __LINE__, \"\", \"%Error: No delays in the "
-                 "design\");\n");
+            puts("VL_FATAL_MT(__FILE__, __LINE__, \"\", \"No delays in the design\");\n");
             puts("return 0;\n}\n");
         }