diff --git a/src/interfaces/chain.cpp b/src/interfaces/chain.cpp
index c12215cd6..f88860687 100644
--- a/src/interfaces/chain.cpp
+++ b/src/interfaces/chain.cpp
@@ -6,6 +6,8 @@
 
 #include <chain.h>
 #include <chainparams.h>
+#include <policy/fees.h>
+#include <policy/policy.h>
 #include <policy/rbf.h>
 #include <primitives/block.h>
 #include <sync.h>
@@ -214,6 +216,18 @@ public:
         return ::mempool.CalculateMemPoolAncestors(entry, ancestors, limit_ancestor_count, limit_ancestor_size,
             limit_descendant_count, limit_descendant_size, unused_error_string);
     }
+    CFeeRate estimateSmartFee(int num_blocks, bool conservative, FeeCalculation* calc) override
+    {
+        return ::feeEstimator.estimateSmartFee(num_blocks, calc, conservative);
+    }
+    unsigned int estimateMaxBlocks() override
+    {
+        return ::feeEstimator.HighestTargetTracked(FeeEstimateHorizon::LONG_HALFLIFE);
+    }
+    CFeeRate mempoolMinFee() override
+    {
+        return ::mempool.GetMinFee(gArgs.GetArg("-maxmempool", DEFAULT_MAX_MEMPOOL_SIZE) * 1000000);
+    }
 };
 
 } // namespace
diff --git a/src/interfaces/chain.h b/src/interfaces/chain.h
index 2e0328eb2..d0f74cb10 100644
--- a/src/interfaces/chain.h
+++ b/src/interfaces/chain.h
@@ -19,6 +19,7 @@ class CScheduler;
 class CTransaction;
 class uint256;
 struct CBlockLocator;
+struct FeeCalculation;
 
 namespace interfaces {
 
@@ -145,6 +146,15 @@ public:
 
     //! Check chain limits.
     virtual bool checkChainLimits(CTransactionRef tx) = 0;
+
+    //! Estimate smart fee.
+    virtual CFeeRate estimateSmartFee(int num_blocks, bool conservative, FeeCalculation* calc = nullptr) = 0;
+
+    //! Fee estimator max target.
+    virtual unsigned int estimateMaxBlocks() = 0;
+
+    //! Pool min fee.
+    virtual CFeeRate mempoolMinFee() = 0;
 };
 
 //! Interface to let node manage chain clients (wallets, or maybe tools for
diff --git a/src/interfaces/wallet.cpp b/src/interfaces/wallet.cpp
index e870d3d53..f3a0b416d 100644
--- a/src/interfaces/wallet.cpp
+++ b/src/interfaces/wallet.cpp
@@ -457,7 +457,7 @@ public:
     {
         FeeCalculation fee_calc;
         CAmount result;
-        result = GetMinimumFee(*m_wallet, tx_bytes, coin_control, ::mempool, ::feeEstimator, &fee_calc);
+        result = GetMinimumFee(*m_wallet, tx_bytes, coin_control, &fee_calc);
         if (returned_target) *returned_target = fee_calc.returnedTarget;
         if (reason) *reason = fee_calc.reason;
         return result;
diff --git a/src/rpc/mining.cpp b/src/rpc/mining.cpp
index 6625a03bb..f2acb8fbf 100644
--- a/src/rpc/mining.cpp
+++ b/src/rpc/mining.cpp
@@ -843,7 +843,8 @@ static UniValue estimatesmartfee(const JSONRPCRequest& request)
 
     RPCTypeCheck(request.params, {UniValue::VNUM, UniValue::VSTR});
     RPCTypeCheckArgument(request.params[0], UniValue::VNUM);
-    unsigned int conf_target = ParseConfirmTarget(request.params[0]);
+    unsigned int max_target = ::feeEstimator.HighestTargetTracked(FeeEstimateHorizon::LONG_HALFLIFE);
+    unsigned int conf_target = ParseConfirmTarget(request.params[0], max_target);
     bool conservative = true;
     if (!request.params[1].isNull()) {
         FeeEstimateMode fee_mode;
@@ -915,7 +916,8 @@ static UniValue estimaterawfee(const JSONRPCRequest& request)
 
     RPCTypeCheck(request.params, {UniValue::VNUM, UniValue::VNUM}, true);
     RPCTypeCheckArgument(request.params[0], UniValue::VNUM);
-    unsigned int conf_target = ParseConfirmTarget(request.params[0]);
+    unsigned int max_target = ::feeEstimator.HighestTargetTracked(FeeEstimateHorizon::LONG_HALFLIFE);
+    unsigned int conf_target = ParseConfirmTarget(request.params[0], max_target);
     double threshold = 0.95;
     if (!request.params[1].isNull()) {
         threshold = request.params[1].get_real();
diff --git a/src/rpc/util.cpp b/src/rpc/util.cpp
index 1eec916ab..fb048311d 100644
--- a/src/rpc/util.cpp
+++ b/src/rpc/util.cpp
@@ -4,11 +4,9 @@
 
 #include <key_io.h>
 #include <keystore.h>
-#include <policy/fees.h>
 #include <rpc/util.h>
 #include <tinyformat.h>
 #include <util/strencodings.h>
-#include <validation.h>
 
 InitInterfaces* g_rpc_interfaces = nullptr;
 
@@ -130,10 +128,9 @@ UniValue DescribeAddress(const CTxDestination& dest)
     return boost::apply_visitor(DescribeAddressVisitor(), dest);
 }
 
-unsigned int ParseConfirmTarget(const UniValue& value)
+unsigned int ParseConfirmTarget(const UniValue& value, unsigned int max_target)
 {
     int target = value.get_int();
-    unsigned int max_target = ::feeEstimator.HighestTargetTracked(FeeEstimateHorizon::LONG_HALFLIFE);
     if (target < 1 || (unsigned int)target > max_target) {
         throw JSONRPCError(RPC_INVALID_PARAMETER, strprintf("Invalid conf_target, must be between %u - %u", 1, max_target));
     }
diff --git a/src/rpc/util.h b/src/rpc/util.h
index a83ae98b7..e1a5491de 100644
--- a/src/rpc/util.h
+++ b/src/rpc/util.h
@@ -33,7 +33,7 @@ CScript CreateMultisigRedeemscript(const int required, const std::vector<CPubKey
 UniValue DescribeAddress(const CTxDestination& dest);
 
 //! Parse a confirm target option and raise an RPC error if it is invalid.
-unsigned int ParseConfirmTarget(const UniValue& value);
+unsigned int ParseConfirmTarget(const UniValue& value, unsigned int max_target);
 
 RPCErrorCode RPCErrorFromTransactionError(TransactionError terr);
 UniValue JSONRPCTransactionError(TransactionError terr, const std::string& err_string = "");
diff --git a/src/wallet/feebumper.cpp b/src/wallet/feebumper.cpp
index f4b419ca2..dd4b2fad4 100644
--- a/src/wallet/feebumper.cpp
+++ b/src/wallet/feebumper.cpp
@@ -144,7 +144,7 @@ Result CreateTransaction(const CWallet* wallet, const uint256& txid, const CCoin
         new_fee = total_fee;
         nNewFeeRate = CFeeRate(total_fee, maxNewTxSize);
     } else {
-        new_fee = GetMinimumFee(*wallet, maxNewTxSize, coin_control, mempool, ::feeEstimator, nullptr /* FeeCalculation */);
+        new_fee = GetMinimumFee(*wallet, maxNewTxSize, coin_control, nullptr /* FeeCalculation */);
         nNewFeeRate = CFeeRate(new_fee, maxNewTxSize);
 
         // New fee rate must be at least old rate + minimum incremental relay rate
@@ -195,7 +195,7 @@ Result CreateTransaction(const CWallet* wallet, const uint256& txid, const CCoin
 
     // If the output would become dust, discard it (converting the dust to fee)
     poutput->nValue -= nDelta;
-    if (poutput->nValue <= GetDustThreshold(*poutput, GetDiscardRate(*wallet, ::feeEstimator))) {
+    if (poutput->nValue <= GetDustThreshold(*poutput, GetDiscardRate(*wallet))) {
         wallet->WalletLogPrintf("Bumping fee and discarding dust output\n");
         new_fee += poutput->nValue;
         mtx.vout.erase(mtx.vout.begin() + nOutput);
diff --git a/src/wallet/fees.cpp b/src/wallet/fees.cpp
index 9e2984ff0..545adaebc 100644
--- a/src/wallet/fees.cpp
+++ b/src/wallet/fees.cpp
@@ -6,7 +6,6 @@
 #include <wallet/fees.h>
 
 #include <policy/policy.h>
-#include <txmempool.h>
 #include <util/system.h>
 #include <validation.h>
 #include <wallet/coincontrol.h>
@@ -19,9 +18,9 @@ CAmount GetRequiredFee(const CWallet& wallet, unsigned int nTxBytes)
 }
 
 
-CAmount GetMinimumFee(const CWallet& wallet, unsigned int nTxBytes, const CCoinControl& coin_control, const CTxMemPool& pool, const CBlockPolicyEstimator& estimator, FeeCalculation* feeCalc)
+CAmount GetMinimumFee(const CWallet& wallet, unsigned int nTxBytes, const CCoinControl& coin_control, FeeCalculation* feeCalc)
 {
-    CAmount fee_needed = GetMinimumFeeRate(wallet, coin_control, pool, estimator, feeCalc).GetFee(nTxBytes);
+    CAmount fee_needed = GetMinimumFeeRate(wallet, coin_control, feeCalc).GetFee(nTxBytes);
     // Always obey the maximum
     if (fee_needed > maxTxFee) {
         fee_needed = maxTxFee;
@@ -35,7 +34,7 @@ CFeeRate GetRequiredFeeRate(const CWallet& wallet)
     return std::max(wallet.m_min_fee, ::minRelayTxFee);
 }
 
-CFeeRate GetMinimumFeeRate(const CWallet& wallet, const CCoinControl& coin_control, const CTxMemPool& pool, const CBlockPolicyEstimator& estimator, FeeCalculation* feeCalc)
+CFeeRate GetMinimumFeeRate(const CWallet& wallet, const CCoinControl& coin_control, FeeCalculation* feeCalc)
 {
     /* User control of how to calculate fee uses the following parameter precedence:
        1. coin_control.m_feerate
@@ -64,7 +63,7 @@ CFeeRate GetMinimumFeeRate(const CWallet& wallet, const CCoinControl& coin_contr
         if (coin_control.m_fee_mode == FeeEstimateMode::CONSERVATIVE) conservative_estimate = true;
         else if (coin_control.m_fee_mode == FeeEstimateMode::ECONOMICAL) conservative_estimate = false;
 
-        feerate_needed = estimator.estimateSmartFee(target, feeCalc, conservative_estimate);
+        feerate_needed = wallet.chain().estimateSmartFee(target, conservative_estimate, feeCalc);
         if (feerate_needed == CFeeRate(0)) {
             // if we don't have enough data for estimateSmartFee, then use fallback fee
             feerate_needed = wallet.m_fallback_fee;
@@ -74,7 +73,7 @@ CFeeRate GetMinimumFeeRate(const CWallet& wallet, const CCoinControl& coin_contr
             if (wallet.m_fallback_fee == CFeeRate(0)) return feerate_needed;
         }
         // Obey mempool min fee when using smart fee estimation
-        CFeeRate min_mempool_feerate = pool.GetMinFee(gArgs.GetArg("-maxmempool", DEFAULT_MAX_MEMPOOL_SIZE) * 1000000);
+        CFeeRate min_mempool_feerate = wallet.chain().mempoolMinFee();
         if (feerate_needed < min_mempool_feerate) {
             feerate_needed = min_mempool_feerate;
             if (feeCalc) feeCalc->reason = FeeReason::MEMPOOL_MIN;
@@ -90,10 +89,10 @@ CFeeRate GetMinimumFeeRate(const CWallet& wallet, const CCoinControl& coin_contr
     return feerate_needed;
 }
 
-CFeeRate GetDiscardRate(const CWallet& wallet, const CBlockPolicyEstimator& estimator)
+CFeeRate GetDiscardRate(const CWallet& wallet)
 {
-    unsigned int highest_target = estimator.HighestTargetTracked(FeeEstimateHorizon::LONG_HALFLIFE);
-    CFeeRate discard_rate = estimator.estimateSmartFee(highest_target, nullptr /* FeeCalculation */, false /* conservative */);
+    unsigned int highest_target = wallet.chain().estimateMaxBlocks();
+    CFeeRate discard_rate = wallet.chain().estimateSmartFee(highest_target, false /* conservative */);
     // Don't let discard_rate be greater than longest possible fee estimate if we get a valid fee estimate
     discard_rate = (discard_rate == CFeeRate(0)) ? wallet.m_discard_rate : std::min(discard_rate, wallet.m_discard_rate);
     // Discard rate must be at least dustRelayFee
diff --git a/src/wallet/fees.h b/src/wallet/fees.h
index 6bfee456c..434f211dc 100644
--- a/src/wallet/fees.h
+++ b/src/wallet/fees.h
@@ -8,10 +8,8 @@
 
 #include <amount.h>
 
-class CBlockPolicyEstimator;
 class CCoinControl;
 class CFeeRate;
-class CTxMemPool;
 class CWallet;
 struct FeeCalculation;
 
@@ -25,7 +23,7 @@ CAmount GetRequiredFee(const CWallet& wallet, unsigned int nTxBytes);
  * Estimate the minimum fee considering user set parameters
  * and the required fee
  */
-CAmount GetMinimumFee(const CWallet& wallet, unsigned int nTxBytes, const CCoinControl& coin_control, const CTxMemPool& pool, const CBlockPolicyEstimator& estimator, FeeCalculation* feeCalc);
+CAmount GetMinimumFee(const CWallet& wallet, unsigned int nTxBytes, const CCoinControl& coin_control, FeeCalculation* feeCalc);
 
 /**
  * Return the minimum required feerate taking into account the
@@ -37,11 +35,11 @@ CFeeRate GetRequiredFeeRate(const CWallet& wallet);
  * Estimate the minimum fee rate considering user set parameters
  * and the required fee
  */
-CFeeRate GetMinimumFeeRate(const CWallet& wallet, const CCoinControl& coin_control, const CTxMemPool& pool, const CBlockPolicyEstimator& estimator, FeeCalculation* feeCalc);
+CFeeRate GetMinimumFeeRate(const CWallet& wallet, const CCoinControl& coin_control, FeeCalculation* feeCalc);
 
 /**
  * Return the maximum feerate for discarding change.
  */
-CFeeRate GetDiscardRate(const CWallet& wallet, const CBlockPolicyEstimator& estimator);
+CFeeRate GetDiscardRate(const CWallet& wallet);
 
 #endif // BITCOIN_WALLET_FEES_H
diff --git a/src/wallet/rpcwallet.cpp b/src/wallet/rpcwallet.cpp
index 721779953..09e91dc58 100644
--- a/src/wallet/rpcwallet.cpp
+++ b/src/wallet/rpcwallet.cpp
@@ -424,7 +424,7 @@ static UniValue sendtoaddress(const JSONRPCRequest& request)
     }
 
     if (!request.params[6].isNull()) {
-        coin_control.m_confirm_target = ParseConfirmTarget(request.params[6]);
+        coin_control.m_confirm_target = ParseConfirmTarget(request.params[6], pwallet->chain().estimateMaxBlocks());
     }
 
     if (!request.params[7].isNull()) {
@@ -884,7 +884,7 @@ static UniValue sendmany(const JSONRPCRequest& request)
     }
 
     if (!request.params[6].isNull()) {
-        coin_control.m_confirm_target = ParseConfirmTarget(request.params[6]);
+        coin_control.m_confirm_target = ParseConfirmTarget(request.params[6], pwallet->chain().estimateMaxBlocks());
     }
 
     if (!request.params[7].isNull()) {
@@ -2989,7 +2989,7 @@ void FundTransaction(CWallet* const pwallet, CMutableTransaction& tx, CAmount& f
             if (options.exists("feeRate")) {
                 throw JSONRPCError(RPC_INVALID_PARAMETER, "Cannot specify both conf_target and feeRate");
             }
-            coinControl.m_confirm_target = ParseConfirmTarget(options["conf_target"]);
+            coinControl.m_confirm_target = ParseConfirmTarget(options["conf_target"], pwallet->chain().estimateMaxBlocks());
         }
         if (options.exists("estimate_mode")) {
             if (options.exists("feeRate")) {
@@ -3279,7 +3279,7 @@ static UniValue bumpfee(const JSONRPCRequest& request)
         if (options.exists("confTarget") && options.exists("totalFee")) {
             throw JSONRPCError(RPC_INVALID_PARAMETER, "confTarget and totalFee options should not both be set. Please provide either a confirmation target for fee estimation or an explicit total fee for the transaction.");
         } else if (options.exists("confTarget")) { // TODO: alias this to conf_target
-            coin_control.m_confirm_target = ParseConfirmTarget(options["confTarget"]);
+            coin_control.m_confirm_target = ParseConfirmTarget(options["confTarget"], pwallet->chain().estimateMaxBlocks());
         } else if (options.exists("totalFee")) {
             totalFee = options["totalFee"].get_int64();
             if (totalFee <= 0) {
diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
index 5c95c7ec6..75681e200 100644
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -2485,10 +2485,10 @@ bool CWallet::SelectCoinsMinConf(const CAmount& nTargetValue, const CoinEligibil
         FeeCalculation feeCalc;
         CCoinControl temp;
         temp.m_confirm_target = 1008;
-        CFeeRate long_term_feerate = GetMinimumFeeRate(*this, temp, ::mempool, ::feeEstimator, &feeCalc);
+        CFeeRate long_term_feerate = GetMinimumFeeRate(*this, temp, &feeCalc);
 
         // Calculate cost of change
-        CAmount cost_of_change = GetDiscardRate(*this, ::feeEstimator).GetFee(coin_selection_params.change_spend_size) + coin_selection_params.effective_fee.GetFee(coin_selection_params.change_output_size);
+        CAmount cost_of_change = GetDiscardRate(*this).GetFee(coin_selection_params.change_spend_size) + coin_selection_params.effective_fee.GetFee(coin_selection_params.change_output_size);
 
         // Filter by the min conf specs and add to utxo_pool and calculate effective value
         for (OutputGroup& group : groups) {
@@ -2858,10 +2858,10 @@ bool CWallet::CreateTransaction(interfaces::Chain::Lock& locked_chain, const std
             CTxOut change_prototype_txout(0, scriptChange);
             coin_selection_params.change_output_size = GetSerializeSize(change_prototype_txout);
 
-            CFeeRate discard_rate = GetDiscardRate(*this, ::feeEstimator);
+            CFeeRate discard_rate = GetDiscardRate(*this);
 
             // Get the fee rate to use effective values in coin selection
-            CFeeRate nFeeRateNeeded = GetMinimumFeeRate(*this, coin_control, ::mempool, ::feeEstimator, &feeCalc);
+            CFeeRate nFeeRateNeeded = GetMinimumFeeRate(*this, coin_control, &feeCalc);
 
             nFeeRet = 0;
             bool pick_new_inputs = true;
@@ -2994,7 +2994,7 @@ bool CWallet::CreateTransaction(interfaces::Chain::Lock& locked_chain, const std
                     return false;
                 }
 
-                nFeeNeeded = GetMinimumFee(*this, nBytes, coin_control, ::mempool, ::feeEstimator, &feeCalc);
+                nFeeNeeded = GetMinimumFee(*this, nBytes, coin_control, &feeCalc);
                 if (feeCalc.reason == FeeReason::FALLBACK && !m_allow_fallback_fee) {
                     // eventually allow a fallback fee
                     strFailReason = _("Fee estimation failed. Fallbackfee is disabled. Wait a few blocks or enable -fallbackfee.");
@@ -3022,7 +3022,7 @@ bool CWallet::CreateTransaction(interfaces::Chain::Lock& locked_chain, const std
                     // change output. Only try this once.
                     if (nChangePosInOut == -1 && nSubtractFeeFromAmount == 0 && pick_new_inputs) {
                         unsigned int tx_size_with_change = nBytes + coin_selection_params.change_output_size + 2; // Add 2 as a buffer in case increasing # of outputs changes compact size
-                        CAmount fee_needed_with_change = GetMinimumFee(*this, tx_size_with_change, coin_control, ::mempool, ::feeEstimator, nullptr);
+                        CAmount fee_needed_with_change = GetMinimumFee(*this, tx_size_with_change, coin_control, nullptr);
                         CAmount minimum_value_for_change = GetDustThreshold(change_prototype_txout, discard_rate);
                         if (nFeeRet >= fee_needed_with_change + minimum_value_for_change) {
                             pick_new_inputs = false;
diff --git a/src/wallet/wallet.h b/src/wallet/wallet.h
index 2a5d6caaf..f215765da 100644
--- a/src/wallet/wallet.h
+++ b/src/wallet/wallet.h
@@ -100,8 +100,6 @@ class CCoinControl;
 class COutput;
 class CReserveKey;
 class CScript;
-class CTxMemPool;
-class CBlockPolicyEstimator;
 class CWalletTx;
 struct FeeCalculation;
 enum class FeeEstimateMode;