diff --git a/src/legacy/validation_zerocoin_legacy.cpp b/src/legacy/validation_zerocoin_legacy.cpp
index db58fb0bc3169..6bd16a1d1bb99 100644
--- a/src/legacy/validation_zerocoin_legacy.cpp
+++ b/src/legacy/validation_zerocoin_legacy.cpp
@@ -55,8 +55,8 @@ void DataBaseAccChecksum(const CBlockIndex* pindex, bool fWrite)
         pindex->nAccumulatorCheckpoint == pindex->pprev->nAccumulatorCheckpoint)
         return;
 
-    uint256 accCurr = pindex->nAccumulatorCheckpoint;
-    uint256 accPrev = pindex->pprev->nAccumulatorCheckpoint;
+    arith_uint256 accCurr = UintToArith256(pindex->nAccumulatorCheckpoint);
+    arith_uint256 accPrev = UintToArith256(pindex->pprev->nAccumulatorCheckpoint);
     // add/remove changed checksums to/from DB
     for (int i = (int)libzerocoin::zerocoinDenomList.size()-1; i >= 0; i--) {
         const uint32_t& nChecksum = accCurr.Get32();
diff --git a/src/libzerocoin/Coin.cpp b/src/libzerocoin/Coin.cpp
index d5cb6c2614915..d889e78f336ce 100644
--- a/src/libzerocoin/Coin.cpp
+++ b/src/libzerocoin/Coin.cpp
@@ -62,8 +62,8 @@ int ExtractVersionFromSerial(const CBigNum& bnSerial)
 {
     try {
         //Serial is marked as v2 only if the first byte is 0xF
-        uint256 nMark = bnSerial.getuint256() >> (256 - V2_BITSHIFT);
-        if (nMark == 0xf)
+        arith_uint256 nMark = bnSerial.getuint256() >> (256 - V2_BITSHIFT);
+        if (nMark == arith_uint256(0xf))
             return PUBKEY_VERSION;
     } catch (const std::range_error& e) {
         //std::cout << "ExtractVersionFromSerial(): " << e.what() << std::endl;
@@ -77,8 +77,7 @@ int ExtractVersionFromSerial(const CBigNum& bnSerial)
 //Remove the first four bits for V2 serials
 CBigNum GetAdjustedSerial(const CBigNum& bnSerial)
 {
-    uint256 serial = bnSerial.getuint256();
-    serial &= ~UINT256_ZERO >> V2_BITSHIFT;
+    const uint256& serial = ArithToUint256(bnSerial.getuint256() & (~ARITH_UINT256_ZERO >> V2_BITSHIFT));
     CBigNum bnSerialAdjusted;
     bnSerialAdjusted.setuint256(serial);
     return bnSerialAdjusted;
@@ -108,9 +107,9 @@ bool IsValidCommitmentToCoinRange(const ZerocoinParams* params, const CBigNum& b
 
 CBigNum ExtractSerialFromPubKey(const CPubKey pubkey)
 {
-    uint256 hashedPubkey = Hash(pubkey.begin(), pubkey.end()) >> V2_BITSHIFT;
-    uint256 uintSerial = (uint256(0xF) << (256 - V2_BITSHIFT)) | hashedPubkey;
-    return CBigNum(uintSerial);
+    const arith_uint256& hashedPubkey = UintToArith256(Hash(pubkey.begin(), pubkey.end())) >> V2_BITSHIFT;
+    arith_uint256 uintSerial = (arith_uint256(0xF) << (256 - V2_BITSHIFT)) | hashedPubkey;
+    return CBigNum(ArithToUint256(uintSerial));
 }
 
 
diff --git a/src/libzerocoin/CoinSpend.cpp b/src/libzerocoin/CoinSpend.cpp
index d0caf8e901595..e13c25b442fa3 100644
--- a/src/libzerocoin/CoinSpend.cpp
+++ b/src/libzerocoin/CoinSpend.cpp
@@ -52,7 +52,7 @@ bool CoinSpend::HasValidSignature() const
 
     try {
         //V2 serial requires that the signature hash be signed by the public key associated with the serial
-        uint256 hashedPubkey = Hash(pubkey.begin(), pubkey.end()) >> V2_BITSHIFT;
+        arith_uint256 hashedPubkey = UintToArith256(Hash(pubkey.begin(), pubkey.end())) >> V2_BITSHIFT;
         if (hashedPubkey != GetAdjustedSerial(coinSerialNumber).getuint256()) {
             //cout << "CoinSpend::HasValidSignature() hashedpubkey is not equal to the serial!\n";
             return false;
diff --git a/src/libzerocoin/bignum.cpp b/src/libzerocoin/bignum.cpp
index 20de4431744ad..3a05b2a9fd27a 100644
--- a/src/libzerocoin/bignum.cpp
+++ b/src/libzerocoin/bignum.cpp
@@ -110,14 +110,14 @@ void CBigNum::setuint256(uint256 n)
     mpz_import(bn, n.size(), -1, 1, 0, 0, (unsigned char*)&n);
 }
 
-uint256 CBigNum::getuint256() const
+arith_uint256 CBigNum::getuint256() const
 {
     if(bitSize() > 256) {
         throw std::range_error("cannot convert to uint256, bignum longer than 256 bits");
     }
     uint256 n = UINT256_ZERO;
     mpz_export((unsigned char*)&n, NULL, -1, 1, 0, 0, bn);
-    return n;
+    return UintToArith256(n);
 }
 
 void CBigNum::setvch(const std::vector<unsigned char>& vch)
diff --git a/src/libzerocoin/bignum.h b/src/libzerocoin/bignum.h
index 4cacb2f8104b6..4978d589f46ba 100755
--- a/src/libzerocoin/bignum.h
+++ b/src/libzerocoin/bignum.h
@@ -17,6 +17,7 @@
 #include <vector>
 #include <limits.h>
 
+#include "arith_uint256.h"
 #include "serialize.h"
 #include "uint256.h"
 #include "version.h"
@@ -72,7 +73,7 @@ class CBigNum
     void setint64(int64_t sn);
     void setuint64(uint64_t n);
     void setuint256(uint256 n);
-    uint256 getuint256() const;
+    arith_uint256 getuint256() const;
     void setvch(const std::vector<unsigned char>& vch);
     std::vector<unsigned char> getvch() const;
     void SetDec(const std::string& str);
diff --git a/src/zpiv/zpos.cpp b/src/zpiv/zpos.cpp
index 26867ef709fe2..8b887b4c49f41 100644
--- a/src/zpiv/zpos.cpp
+++ b/src/zpiv/zpos.cpp
@@ -18,8 +18,7 @@ uint32_t ParseAccChecksum(uint256 nCheckpoint, const libzerocoin::CoinDenominati
 {
     int pos = std::distance(libzerocoin::zerocoinDenomList.begin(),
             find(libzerocoin::zerocoinDenomList.begin(), libzerocoin::zerocoinDenomList.end(), denom));
-    nCheckpoint = nCheckpoint >> (32*((libzerocoin::zerocoinDenomList.size() - 1) - pos));
-    return nCheckpoint.Get32();
+    return (UintToArith256(nCheckpoint) >> (32*((libzerocoin::zerocoinDenomList.size() - 1) - pos))).Get32();
 }
 
 bool CLegacyZPivStake::InitFromTxIn(const CTxIn& txin)
@@ -47,7 +46,7 @@ CLegacyZPivStake::CLegacyZPivStake(const libzerocoin::CoinSpend& spend) : CStake
 {
     this->nChecksum = spend.getAccumulatorChecksum();
     this->denom = spend.getDenomination();
-    uint256 nSerial = spend.getCoinSerialNumber().getuint256();
+    arith_uint256 nSerial = spend.getCoinSerialNumber().getuint256();
     this->hashSerial = Hash(nSerial.begin(), nSerial.end());
 }