diff --git a/elab_type.cc b/elab_type.cc
index 338926ef1..413e6f61c 100644
--- a/elab_type.cc
+++ b/elab_type.cc
@@ -141,6 +141,7 @@ ivl_type_t vector_type_t::elaborate_type_raw(Design*des, NetScope*scope) const
       netvector_t*tmp = new netvector_t(packed, base_type);
       tmp->set_signed(signed_flag);
       tmp->set_isint(integer_flag);
+      tmp->set_implicit(implicit_flag);
 
       return tmp;
 }
diff --git a/ivtest/ivltests/parameter_1bit.v b/ivtest/ivltests/parameter_1bit.v
new file mode 100644
index 000000000..bf59e5b5c
--- /dev/null
+++ b/ivtest/ivltests/parameter_1bit.v
@@ -0,0 +1,26 @@
+// Check that parameters with a implicit and 1-bit range type are handled correctly
+
+module test #(
+  // This should get truncated to 1'b1
+  parameter [0:0] P = 2'b11
+);
+
+  reg failed = 1'b0;
+
+  `define check(expr, val) \
+    if (expr !== val) begin \
+      $display("FAILED: `%s`, expected %0d, got %0d", `"expr`", val, expr); \
+      failed = 1'b1; \
+    end
+
+  initial begin
+    `check($bits(P), 1);
+    `check(P + 1'b1, 1'b0);
+    `check(P, 1'b1);
+
+    if (!failed) begin
+      $display("PASSED");
+    end
+  end
+
+endmodule
diff --git a/ivtest/ivltests/parameter_scalar.v b/ivtest/ivltests/parameter_scalar.v
new file mode 100644
index 000000000..069193e60
--- /dev/null
+++ b/ivtest/ivltests/parameter_scalar.v
@@ -0,0 +1,26 @@
+// Check that parameters with a scalar type are handled correctly
+
+module test #(
+  // This should get truncated to 1'b1
+  parameter bit P = 2'b11
+);
+
+  bit failed = 1'b0;
+
+  `define check(expr, val) \
+    if (expr !== val) begin \
+      $display("FAILED: `%s`, expected %0d, got %0d", `"expr`", val, expr); \
+      failed = 1'b1; \
+    end
+
+  initial begin
+    `check($bits(P), 1);
+    `check(P + 1'b1, 1'b0);
+    `check(P, 1'b1);
+
+    if (!failed) begin
+      $display("PASSED");
+    end
+  end
+
+endmodule
diff --git a/ivtest/regress-sv.list b/ivtest/regress-sv.list
index 65140e653..2aa6adcbe 100644
--- a/ivtest/regress-sv.list
+++ b/ivtest/regress-sv.list
@@ -374,6 +374,7 @@ parameter_no_default_fail2 CE			ivltests
 parameter_no_default_toplvl normal,-g2005-sv	ivltests
 parameter_override_invalid7 CE,-g2005-sv	ivltests
 parameter_override_invalid8 CE,-g2005-sv	ivltests
+parameter_scalar	normal,-g2005-sv	ivltests
 parameter_type2		normal,-g2009		ivltests
 parpkg_test		normal,-g2009		ivltests
 parpkg_test2		normal,-g2009		ivltests
diff --git a/ivtest/regress-vlg.list b/ivtest/regress-vlg.list
index 5f32b39d2..3bd41a707 100644
--- a/ivtest/regress-vlg.list
+++ b/ivtest/regress-vlg.list
@@ -712,6 +712,7 @@ param_test2		normal			ivltests gold=param_test2.gold
 param_test3		normal			ivltests gold=param_test3.gold # PR#293
 param_test4		normal			ivltests
 param_times		normal			ivltests # param has multiplication.
+parameter_1bit		normal			ivltests
 parameter_type		normal			ivltests gold=parameter_type.gold
 parameter_in_generate1	CE			ivltests
 parameter_no_default	CE			ivltests
diff --git a/net_design.cc b/net_design.cc
index 8112f2039..ac579bb51 100644
--- a/net_design.cc
+++ b/net_design.cc
@@ -515,8 +515,7 @@ void NetScope::evaluate_parameter_logic_(Design*des, param_ref_t cur)
       // case of a netvector_t with no dimensions, that exists only to carry
       // signed-ness, e.g.:
       //  parameter signed foo = bar;
-      // (Scalars are handled differently, not by a netvector_t with no
-      // dimensions.)
+      // These will be marked as scalar, but also have the implict flag set.
       const netvector_t* param_vect = dynamic_cast<const netvector_t*> (param_type);
 
       if (debug_elaborate) {
@@ -536,8 +535,9 @@ void NetScope::evaluate_parameter_logic_(Design*des, param_ref_t cur)
       int lv_width = -2;
       if (param_type) {
 	    use_type = param_type->base_type();
-	    // Is this a netvector_t with no dimenions?
-	    if (param_vect && param_vect->packed_dims().size()==0)
+	    // Is this an implicit netvector_t with no dimenions?
+	    if (param_vect && param_vect->get_implicit() &&
+	        param_vect->get_scalar())
 		  lv_width = -2;
 	    else if (param_type->packed())
 		  lv_width = param_type->packed_width();
diff --git a/netvector.cc b/netvector.cc
index 86f3d1637..f43dd839e 100644
--- a/netvector.cc
+++ b/netvector.cc
@@ -50,13 +50,13 @@ const netvector_t* netvector_t::integer_type(bool is_signed)
 netvector_t netvector_t::scalar_logic (IVL_VT_LOGIC);
 
 netvector_t::netvector_t(ivl_variable_type_t type, long msb, long lsb, bool flag)
-: type_(type), signed_(flag), isint_(false)
+: type_(type), signed_(flag), isint_(false), implicit_(false)
 {
       packed_dims_.push_back(netrange_t(msb,lsb));
 }
 
 netvector_t::netvector_t(ivl_variable_type_t type)
-: type_(type), signed_(false), isint_(false)
+: type_(type), signed_(false), isint_(false), implicit_(false)
 {
 }
 
diff --git a/netvector.h b/netvector.h
index c79672900..55a482ec8 100644
--- a/netvector.h
+++ b/netvector.h
@@ -56,6 +56,9 @@ class netvector_t : public ivl_type_s {
 
       inline bool get_scalar(void) const { return packed_dims_.empty(); }
 
+      void set_implicit(bool implicit) { implicit_ = implicit; }
+      bool get_implicit() const { return implicit_; }
+
       ivl_variable_type_t base_type() const;
       const std::vector<netrange_t>&packed_dims() const;
 
@@ -89,6 +92,7 @@ class netvector_t : public ivl_type_s {
       ivl_variable_type_t type_;
       bool signed_    : 1;
       bool isint_     : 1;		// original type of integer
+      bool implicit_  : 1;
 };
 
 inline netvector_t::netvector_t(const std::vector<netrange_t>&pd,