Take precision settings into consideration.

js/src/components/paid-ads/validateCampaign.js

@@ -31,18 +31,21 @@ const validateCampaign = ( values, opts ) => {
 		Number.isFinite( opts?.dailyBudget )
 	) {
 		const { amount } = values;
-		const { dailyBudget, formatAmount } = opts;
-		const minAmount = Math.round( dailyBudget * BUDGET_MIN_PERCENT );
+		const { dailyBudget, formatAmount, precision } = opts;
+
+		const minAmount = parseFloat(
+			( dailyBudget * BUDGET_MIN_PERCENT ).toFixed( precision )
+		);
 
 		if ( amount < minAmount ) {
 			return {
 				amount: sprintf(
 					/* translators: %1$s: minimum daily budget */
 					__(
-						'Please make sure daily average cost is greater than %s.',
+						'Please make sure daily average cost is at least %s.',
 						'google-listings-and-ads'
 					),
-					formatAmount( minAmount - 1 )
+					formatAmount( minAmount )
 				),
 			};
 		}

js/src/hooks/useValidateCampaignWithCountryCodes.js

@@ -25,6 +25,7 @@ import getHighestBudget from '.~/utils/getHighestBudget';
  * @property {(values: CampaignFormValues) => Object} validateCampaignWithCountryCodes A function to validate campaign form values.
  * @property {number | undefined} dailyBudget The daily budget recommendation.
  * @property {(number: string | number) => string} formatAmount A function to format an amount according to the user's currency settings.
+ * @property {number} precision Number of decimal places after the decimal separator.
  * @property {(countryCodes: Array<CountryCode>) => void} refreshCountryCodes A function to refresh the country codes.
  * @property {string} currencyCode The currency code.
  * @property {boolean} loaded A boolean indicating whether the budget recommendation data has been resolved and the code currency available.
@@ -39,7 +40,7 @@ import getHighestBudget from '.~/utils/getHighestBudget';
 const useValidateCampaignWithCountryCodes = ( initialCountryCodes ) => {
 	const {
 		formatAmount,
-		adsCurrencyConfig: { code },
+		adsCurrencyConfig: { code, precision },
 	} = useAdsCurrency();
 	const [ countryCodes, setCountryCodes ] = useState( [] );
 
@@ -60,6 +61,7 @@ const useValidateCampaignWithCountryCodes = ( initialCountryCodes ) => {
 					formatAmount,
 					refreshCountryCodes: setCountryCodes,
 					currencyCode: code,
+					precision,
 					loaded: true,
 				};
 			}
@@ -85,19 +87,21 @@ const useValidateCampaignWithCountryCodes = ( initialCountryCodes ) => {
 				return validateCampaign( values, {
 					dailyBudget: budget?.daily_budget,
 					formatAmount,
+					precision,
 				} );
 			};
 
 			return {
 				validateCampaignWithCountryCodes,
 				dailyBudget: budget?.daily_budget,
 				formatAmount,
+				precision,
 				refreshCountryCodes: setCountryCodes,
 				currencyCode: code,
 				loaded,
 			};
 		},
-		[ countryCodes, formatAmount, code, initialCountryCodes ]
+		[ countryCodes, formatAmount, code, initialCountryCodes, precision ]
 	);
 };