diff --git a/src/main/java/org/apache/commons/beanutils/locale/converters/BigDecimalLocaleConverter.java b/src/main/java/org/apache/commons/beanutils/locale/converters/BigDecimalLocaleConverter.java
index 6040c2d0a..c9dbb4082 100644
--- a/src/main/java/org/apache/commons/beanutils/locale/converters/BigDecimalLocaleConverter.java
+++ b/src/main/java/org/apache/commons/beanutils/locale/converters/BigDecimalLocaleConverter.java
@@ -182,4 +182,9 @@ protected Object parse(final Object value, final String pattern) throws ParseExc
             throw new ConversionException("Suplied number is not of type BigDecimal: " + result);
         }
     }
+
+    @Override
+    protected boolean isParseBigDecimal() {
+        return true;
+    }
 }
diff --git a/src/main/java/org/apache/commons/beanutils/locale/converters/BigIntegerLocaleConverter.java b/src/main/java/org/apache/commons/beanutils/locale/converters/BigIntegerLocaleConverter.java
index 70bb6239d..13bf58b43 100644
--- a/src/main/java/org/apache/commons/beanutils/locale/converters/BigIntegerLocaleConverter.java
+++ b/src/main/java/org/apache/commons/beanutils/locale/converters/BigIntegerLocaleConverter.java
@@ -17,6 +17,7 @@
 
 package org.apache.commons.beanutils.locale.converters;
 
+import java.math.BigDecimal;
 import java.math.BigInteger;
 import java.text.ParseException;
 import java.util.Locale;
@@ -176,6 +177,9 @@ protected Object parse(final Object value, final String pattern) throws ParseExc
         if (result == null || result instanceof BigInteger) {
             return result;
         }
+        if (result instanceof BigDecimal) {
+            return ((BigDecimal) result).toBigInteger();
+        }
         if (result instanceof Number) {
             return BigInteger.valueOf(((Number) result).longValue());
         }
@@ -185,4 +189,9 @@ protected Object parse(final Object value, final String pattern) throws ParseExc
             throw new ConversionException("Suplied number is not of type BigInteger: " + result);
         }
     }
+
+    @Override
+    protected boolean isParseBigDecimal() {
+        return true;
+    }
 }
diff --git a/src/main/java/org/apache/commons/beanutils/locale/converters/DecimalLocaleConverter.java b/src/main/java/org/apache/commons/beanutils/locale/converters/DecimalLocaleConverter.java
index e35123493..acf9af723 100644
--- a/src/main/java/org/apache/commons/beanutils/locale/converters/DecimalLocaleConverter.java
+++ b/src/main/java/org/apache/commons/beanutils/locale/converters/DecimalLocaleConverter.java
@@ -178,6 +178,18 @@ public DecimalLocaleConverter(final Object defaultValue, final Locale locale, fi
      * @throws org.apache.commons.beanutils.ConversionException if conversion cannot be performed successfully.
      * @throws ParseException                                   if an error occurs parsing a String to a Number.
      */
+    /**
+     * Tests whether the underlying {@link DecimalFormat} should parse into a {@link java.math.BigDecimal} so that magnitude and precision are preserved.
+     * Subclasses that build {@link java.math.BigInteger} or {@link java.math.BigDecimal} values override this to return {@code true}; the narrowing converters
+     * keep the default {@code Long} / {@code Double} result.
+     *
+     * @return {@code true} to parse into a {@link java.math.BigDecimal}, {@code false} otherwise.
+     * @since 1.11.1
+     */
+    protected boolean isParseBigDecimal() {
+        return false;
+    }
+
     @Override
     protected Object parse(final Object value, final String pattern) throws ParseException {
         if (value instanceof Number) {
@@ -188,6 +200,7 @@ protected Object parse(final Object value, final String pattern) throws ParseExc
         // representation, each call to getInstance actually returns a new
         // object.
         final DecimalFormat formatter = (DecimalFormat) NumberFormat.getInstance(locale);
+        formatter.setParseBigDecimal(isParseBigDecimal());
         // if some constructors default pattern to null, it makes only sense
         // to handle null pattern gracefully
         if (pattern != null) {
diff --git a/src/test/java/org/apache/commons/beanutils/locale/converters/BigDecimalLocaleConverterTest.java b/src/test/java/org/apache/commons/beanutils/locale/converters/BigDecimalLocaleConverterTest.java
index 4cac72eda..646d4973f 100644
--- a/src/test/java/org/apache/commons/beanutils/locale/converters/BigDecimalLocaleConverterTest.java
+++ b/src/test/java/org/apache/commons/beanutils/locale/converters/BigDecimalLocaleConverterTest.java
@@ -228,5 +228,13 @@ public void testConstructorMain() {
 
     }
 
+    /**
+     * Test that a value beyond {@code double} precision is preserved instead of being rounded to a lossy {@code 1.0E+19}.
+     */
+    public void testConvertLargeValueKeepsPrecision() {
+        converter = new BigDecimalLocaleConverter();
+        convertValueNoPattern(converter, "9999999999999999999", new BigDecimal("9999999999999999999"));
+    }
+
 }
 
diff --git a/src/test/java/org/apache/commons/beanutils/locale/converters/BigIntegerLocaleConverterTest.java b/src/test/java/org/apache/commons/beanutils/locale/converters/BigIntegerLocaleConverterTest.java
index acf3ece1e..909ffcb54 100644
--- a/src/test/java/org/apache/commons/beanutils/locale/converters/BigIntegerLocaleConverterTest.java
+++ b/src/test/java/org/apache/commons/beanutils/locale/converters/BigIntegerLocaleConverterTest.java
@@ -229,6 +229,15 @@ public void testConstructorMain() {
 
     }
 
+    /**
+     * Test that a value beyond {@code long} range keeps its full magnitude instead of being clamped to {@code Long.MAX_VALUE}.
+     */
+    public void testConvertLargeValueKeepsMagnitude() {
+        converter = new BigIntegerLocaleConverter();
+        convertValueNoPattern(converter, "9999999999999999999", new BigInteger("9999999999999999999"));
+        convertValueNoPattern(converter, "123456789012345678901234567890", new BigInteger("123456789012345678901234567890"));
+    }
+
     /**
      * Tries to convert to an unsupported type. This tests behavior of the base
      * class. All locale converters should react in the same way.