diff --git a/src/frontend/A64/decoder/a64.inc b/src/frontend/A64/decoder/a64.inc
index d8b416c4..a82e252a 100644
--- a/src/frontend/A64/decoder/a64.inc
+++ b/src/frontend/A64/decoder/a64.inc
@@ -853,7 +853,7 @@ INST(USHLL,                  "USHLL, USHLL2",                             "0Q101
 
 // Data Processing - FP and SIMD - Cryptographic three register
 INST(SM3TT1A,                "SM3TT1A",                                   "11001110010mmmmm10ii00nnnnnddddd")
-//INST(SM3TT1B,                "SM3TT1B",                                   "11001110010mmmmm10ii01nnnnnddddd")
+INST(SM3TT1B,                "SM3TT1B",                                   "11001110010mmmmm10ii01nnnnnddddd")
 //INST(SM3TT2A,                "SM3TT2A",                                   "11001110010mmmmm10ii10nnnnnddddd")
 //INST(SM3TT2B,                "SM3TT2B",                                   "11001110010mmmmm10ii11nnnnnddddd")
 
diff --git a/src/frontend/A64/translate/impl/simd_crypto_three_register.cpp b/src/frontend/A64/translate/impl/simd_crypto_three_register.cpp
index a6809576..16c9a84b 100644
--- a/src/frontend/A64/translate/impl/simd_crypto_three_register.cpp
+++ b/src/frontend/A64/translate/impl/simd_crypto_three_register.cpp
@@ -8,30 +8,52 @@
 
 namespace Dynarmic::A64 {
 
-bool TranslatorVisitor::SM3TT1A(Vec Vm, Imm<2> imm2, Vec Vn, Vec Vd) {
-    const IR::U128 d = ir.GetQ(Vd);
-    const IR::U128 m = ir.GetQ(Vm);
-    const IR::U128 n = ir.GetQ(Vn);
+enum class SM3TT1Variant {
+    A,
+    B,
+};
+
+static void SM3TT1(TranslatorVisitor& v, Vec Vm, Imm<2> imm2, Vec Vn, Vec Vd, SM3TT1Variant behavior) {
+    const IR::U128 d = v.ir.GetQ(Vd);
+    const IR::U128 m = v.ir.GetQ(Vm);
+    const IR::U128 n = v.ir.GetQ(Vn);
     const u32 index = imm2.ZeroExtend();
 
-    const IR::U32 top_d = ir.VectorGetElement(32, d, 3);
-    const IR::U32 before_top_d = ir.VectorGetElement(32, d, 2);
-    const IR::U32 after_low_d = ir.VectorGetElement(32, d, 1);
-    const IR::U32 low_d = ir.VectorGetElement(32, d, 0);
-    const IR::U32 top_n = ir.VectorGetElement(32, n, 3);
+    const IR::U32 top_d = v.ir.VectorGetElement(32, d, 3);
+    const IR::U32 before_top_d = v.ir.VectorGetElement(32, d, 2);
+    const IR::U32 after_low_d = v.ir.VectorGetElement(32, d, 1);
+    const IR::U32 low_d = v.ir.VectorGetElement(32, d, 0);
+    const IR::U32 top_n = v.ir.VectorGetElement(32, n, 3);
 
-    const IR::U32 wj_prime = ir.VectorGetElement(32, m, index);
-    const IR::U32 ss2 = ir.Eor(top_n, ir.RotateRight(top_d, ir.Imm8(20)));
-    const IR::U32 tt1 = ir.Eor(after_low_d, ir.Eor(top_d, before_top_d));
-    const IR::U32 final_tt1 = ir.Add(tt1, ir.Add(low_d, ir.Add(ss2, wj_prime)));
+    const IR::U32 wj_prime = v.ir.VectorGetElement(32, m, index);
+    const IR::U32 ss2 = v.ir.Eor(top_n, v.ir.RotateRight(top_d, v.ir.Imm8(20)));
+    const IR::U32 tt1 = [&] {
+        if (behavior == SM3TT1Variant::A) {
+            return v.ir.Eor(after_low_d, v.ir.Eor(top_d, before_top_d));
+        }
+        const IR::U32 tmp1 = v.ir.And(top_d, after_low_d);
+        const IR::U32 tmp2 = v.ir.And(top_d, before_top_d);
+        const IR::U32 tmp3 = v.ir.And(after_low_d, before_top_d);
+        return v.ir.Or(v.ir.Or(tmp1, tmp2), tmp3);
+    }();
+    const IR::U32 final_tt1 = v.ir.Add(tt1, v.ir.Add(low_d, v.ir.Add(ss2, wj_prime)));
 
-    const IR::U128 zero_vector = ir.ZeroVector();
-    const IR::U128 tmp1 = ir.VectorSetElement(32, zero_vector, 0, after_low_d);
-    const IR::U128 tmp2 = ir.VectorSetElement(32, tmp1, 1, ir.RotateRight(before_top_d, ir.Imm8(23)));
-    const IR::U128 tmp3 = ir.VectorSetElement(32, tmp2, 2, top_d);
-    const IR::U128 result = ir.VectorSetElement(32, tmp3, 3, final_tt1);
+    const IR::U128 zero_vector = v.ir.ZeroVector();
+    const IR::U128 tmp1 = v.ir.VectorSetElement(32, zero_vector, 0, after_low_d);
+    const IR::U128 tmp2 = v.ir.VectorSetElement(32, tmp1, 1, v.ir.RotateRight(before_top_d, v.ir.Imm8(23)));
+    const IR::U128 tmp3 = v.ir.VectorSetElement(32, tmp2, 2, top_d);
+    const IR::U128 result = v.ir.VectorSetElement(32, tmp3, 3, final_tt1);
 
-    ir.SetQ(Vd, result);
+    v.ir.SetQ(Vd, result);
+}
+
+bool TranslatorVisitor::SM3TT1A(Vec Vm, Imm<2> imm2, Vec Vn, Vec Vd) {
+    SM3TT1(*this, Vm, imm2, Vn, Vd, SM3TT1Variant::A);
+    return true;
+}
+
+bool TranslatorVisitor::SM3TT1B(Vec Vm, Imm<2> imm2, Vec Vn, Vec Vd) {
+    SM3TT1(*this, Vm, imm2, Vn, Vd, SM3TT1Variant::B);
     return true;
 }