diff --git a/src/policy/feerate.cpp b/src/policy/feerate.cpp
index f62835acbcf..7cc07099daa 100644
--- a/src/policy/feerate.cpp
+++ b/src/policy/feerate.cpp
@@ -7,6 +7,7 @@
 #include <policy/feerate.h>
 #include <tinyformat.h>
 
+#include <cstdlib>
 
 CFeeRate::CFeeRate(const CAmount& nFeePaid, int32_t virtual_bytes)
 {
@@ -29,9 +30,16 @@ CAmount CFeeRate::GetFee(int32_t virtual_bytes) const
 std::string CFeeRate::ToString(FeeRateFormat fee_rate_format) const
 {
     const CAmount feerate_per_kvb{GetFeePerK()};
+    const auto format_feerate = [](const CAmount fee_rate, const CAmount divisor, const int decimals, const std::string& currency_unit, const std::string& size_unit) {
+        Assert(divisor > 0);
+        const char* sign{fee_rate < 0 ? "-" : ""};
+        const CAmount quotient{std::abs(fee_rate / divisor)};
+        const CAmount remainder{std::abs(fee_rate % divisor)};
+        return strprintf("%s%d.%0*d %s/%s", sign, quotient, decimals, remainder, currency_unit, size_unit);
+    };
     switch (fee_rate_format) {
-    case FeeRateFormat::BTC_KVB: return strprintf("%d.%08d %s/kvB", feerate_per_kvb / COIN, feerate_per_kvb % COIN, CURRENCY_UNIT);
-    case FeeRateFormat::SAT_VB: return strprintf("%d.%03d %s/vB", feerate_per_kvb / 1000, feerate_per_kvb % 1000, CURRENCY_ATOM);
+    case FeeRateFormat::BTC_KVB: return format_feerate(feerate_per_kvb, COIN, /*decimals=*/8, CURRENCY_UNIT, "kvB");
+    case FeeRateFormat::SAT_VB: return format_feerate(feerate_per_kvb, 1000, /*decimals=*/3, CURRENCY_ATOM, "vB");
     } // no default case, so the compiler can warn about missing cases
     assert(false);
 }
diff --git a/src/test/amount_tests.cpp b/src/test/amount_tests.cpp
index 0a273a21e74..24c4e93f9be 100644
--- a/src/test/amount_tests.cpp
+++ b/src/test/amount_tests.cpp
@@ -144,6 +144,24 @@ BOOST_AUTO_TEST_CASE(ToStringTest)
     BOOST_CHECK_EQUAL(feeRate.ToString(), "0.00000001 BTC/kvB");
     BOOST_CHECK_EQUAL(feeRate.ToString(FeeRateFormat::BTC_KVB), "0.00000001 BTC/kvB");
     BOOST_CHECK_EQUAL(feeRate.ToString(FeeRateFormat::SAT_VB), "0.001 sat/vB");
+
+    feeRate = CFeeRate(0);
+    BOOST_CHECK_EQUAL(feeRate.ToString(), "0.00000000 BTC/kvB");
+    BOOST_CHECK_EQUAL(feeRate.ToString(FeeRateFormat::BTC_KVB), "0.00000000 BTC/kvB");
+    BOOST_CHECK_EQUAL(feeRate.ToString(FeeRateFormat::SAT_VB), "0.000 sat/vB");
+
+    feeRate = CFeeRate(-1);
+    BOOST_CHECK_EQUAL(feeRate.ToString(), "-0.00000001 BTC/kvB");
+    BOOST_CHECK_EQUAL(feeRate.ToString(FeeRateFormat::BTC_KVB), "-0.00000001 BTC/kvB");
+    BOOST_CHECK_EQUAL(feeRate.ToString(FeeRateFormat::SAT_VB), "-0.001 sat/vB");
+
+    feeRate = CFeeRate(-1000);
+    BOOST_CHECK_EQUAL(feeRate.ToString(), "-0.00001000 BTC/kvB");
+    BOOST_CHECK_EQUAL(feeRate.ToString(FeeRateFormat::SAT_VB), "-1.000 sat/vB");
+
+    feeRate = CFeeRate(-COIN - 1);
+    BOOST_CHECK_EQUAL(feeRate.ToString(), "-1.00000001 BTC/kvB");
+    BOOST_CHECK_EQUAL(feeRate.ToString(FeeRateFormat::SAT_VB), "-100000.001 sat/vB");
 }
 
 BOOST_AUTO_TEST_SUITE_END()