diff --git a/packages/swap/src/helpers/orders/factories/makeOrderCalculations.test.ts b/packages/swap/src/helpers/orders/factories/makeOrderCalculations.test.ts
index 60fbc091fe..0f92ca2463 100644
--- a/packages/swap/src/helpers/orders/factories/makeOrderCalculations.test.ts
+++ b/packages/swap/src/helpers/orders/factories/makeOrderCalculations.test.ts
@@ -3389,4 +3389,126 @@ describe('makeOrderCalculations', () => {
     }
     expect(calculations[0]).toStrictEqual(expectedCalculation)
   })
+  it('should calculate fees and amounts correctly (case 28, pt at buy side)', () => {
+    const pool: Swap.Pool = mocks.mockedPools7[1]!
+    const pools = [pool]
+    const amounts = {
+      sell: {
+        quantity: '1000000',
+        tokenId: 'tokenB',
+      } as Balance.Amount,
+      buy: {
+        quantity: '0',
+        tokenId: 'tokenA',
+      } as Balance.Amount,
+    }
+    const slippage = 0
+    const calculations = makeOrderCalculations({
+      orderType: 'market',
+      amounts: amounts,
+      limitPrice: undefined,
+      slippage: slippage,
+      pools: pools,
+      tokens: {
+        sellInfo: {
+          decimals: 0,
+          id: 'tokenB',
+        },
+        buyInfo: {
+          decimals: 0,
+          id: 'tokenA',
+        },
+        ptInfo: {
+          decimals: 6,
+          id: 'tokenA',
+        },
+        priceDenomination: 0,
+      },
+      lpTokenHeld: {
+        quantity: '50',
+        tokenId: 'tokenX',
+      },
+      side: 'sell',
+      frontendFeeTiers,
+    })
+    const expectedCalculation: SwapOrderCalculation = {
+      order: {
+        side: 'sell',
+        slippage: 0,
+        orderType: 'market',
+        limitPrice: undefined,
+        amounts: {
+          sell: {
+            quantity: '1000000',
+            tokenId: 'tokenB',
+          },
+          buy: {
+            quantity: '0',
+            tokenId: 'tokenA',
+          },
+        },
+        lpTokenHeld: {
+          quantity: '50',
+          tokenId: 'tokenX',
+        },
+      },
+      sides: {
+        sell: {
+          quantity: '1000000',
+          tokenId: 'tokenB',
+        },
+        buy: {
+          quantity: '199',
+          tokenId: 'tokenA',
+        },
+      },
+      cost: {
+        batcherFee: {
+          quantity: '0',
+          tokenId: '',
+        },
+        deposit: {
+          quantity: '0',
+          tokenId: '',
+        },
+        frontendFeeInfo: {
+          discountTier: undefined,
+          fee: {
+            quantity: '0',
+            tokenId: 'tokenA',
+          },
+        },
+        liquidityFee: {
+          quantity: '0',
+          tokenId: 'tokenB',
+        },
+        ptTotalFeeNoFEF: {
+          tokenId: 'tokenA',
+          quantity: '0',
+        },
+        ptTotalFee: {
+          tokenId: 'tokenA',
+          quantity: '0',
+        },
+      },
+      buyAmountWithSlippage: {
+        quantity: '199',
+        tokenId: 'tokenA',
+      },
+      hasSupply: true,
+      prices: {
+        base: '0.5',
+        market: '0.5',
+        withSlippage: '5025.12562814070351758794',
+        withFees: '5025.12562814070351758794',
+        withFeesAndSlippage: '5025.12562814070351758794',
+        difference: '1004925.125628140703517588',
+        withFeesNoFEF: '5025.12562814070351758794',
+        withFeesAndSlippageNoFEF: '5025.12562814070351758794',
+        differenceNoFEF: '1004925.125628140703517588',
+      },
+      pool: pool,
+    }
+    expect(calculations[0]).toStrictEqual(expectedCalculation)
+  })
 })
diff --git a/packages/swap/src/helpers/orders/factories/makeOrderCalculations.ts b/packages/swap/src/helpers/orders/factories/makeOrderCalculations.ts
index bb56adf719..57a102a544 100644
--- a/packages/swap/src/helpers/orders/factories/makeOrderCalculations.ts
+++ b/packages/swap/src/helpers/orders/factories/makeOrderCalculations.ts
@@ -39,6 +39,8 @@ export const makeOrderCalculations = ({
 }>): Array<SwapOrderCalculation> => {
   const isLimit = orderType === 'limit'
   const maybeLimitPrice = isLimit ? limitPrice : undefined
+  const isSellPt = amounts.sell.tokenId === tokens.ptInfo.id
+  const isBuyPt = amounts.buy.tokenId === tokens.ptInfo.id
 
   const calculations = pools.map<SwapOrderCalculation>((pool) => {
     const buy =
@@ -60,8 +62,9 @@ export const makeOrderCalculations = ({
       tokenId: buy.tokenId,
     }
 
-    // pools that with not enough supply will be filtered out
     const isBuyTokenA = buy.tokenId === pool.tokenA.tokenId
+
+    // pools that with not enough supply will be filtered out
     const poolSupply = isBuyTokenA ? pool.tokenA.quantity : pool.tokenB.quantity
     const supplyRequired =
       (!Quantities.isZero(buy.quantity) || !Quantities.isZero(sell.quantity)) &&
@@ -72,24 +75,32 @@ export const makeOrderCalculations = ({
     // lf is sell side % of quantity ie. XToken 100 * 1% = 1 XToken
     const liquidityFee: Balance.Amount = getLiquidityProviderFee(pool.fee, sell)
 
+    // whether sell or buy is PT, then we use the quantity as frontend fee base
+    // otherwise we derive from the ptPrice of the pool of the sell side
     const ptPriceSell = isBuyTokenA
       ? new BigNumber(pool.ptPriceTokenB)
       : new BigNumber(pool.ptPriceTokenA)
+    const sellQuantity = new BigNumber(sell.quantity)
+    const sellPrice = new BigNumber(ptPriceSell)
+    const sellInPtTerms = ptPriceSell.isZero()
+      ? Quantities.zero
+      : asQuantity(
+          sellQuantity
+            .dividedBy(new BigNumber(1).dividedBy(sellPrice))
+            .toString(),
+        )
+    const ptQuantity = isSellPt
+      ? sell.quantity
+      : isBuyPt
+      ? buy.quantity
+      : sellInPtTerms
 
-    // ffee is based on PT value range + LP holding range (sides may need conversion, when none is PT)
-    // TODO: it needs update, prices by muesli are provided in ADA, quantities in atomic units
+    // ffee is based on PT value range + LP holding range
     const frontendFeeInfo = getFrontendFee({
       lpTokenHeld,
-      primaryTokenId: tokens.ptInfo.id,
-      sellInPrimaryTokenValue: {
+      ptAmount: {
         tokenId: tokens.ptInfo.id,
-        quantity: ptPriceSell.isZero()
-          ? Quantities.zero
-          : asQuantity(
-              new BigNumber(sell.quantity)
-                .dividedBy(ptPriceSell)
-                .integerValue(BigNumber.ROUND_CEIL),
-            ),
+        quantity: ptQuantity,
       },
       feeTiers: frontendFeeTiers,
     })
@@ -101,12 +112,14 @@ export const makeOrderCalculations = ({
         ? Quantities.zero
         : new BigNumber(pool.batcherFee.quantity)
             .dividedBy(ptPriceSell)
-            .integerValue(BigNumber.ROUND_CEIL),
+            .integerValue(BigNumber.ROUND_CEIL)
+            .toString(),
       frontendFee: ptPriceSell.isZero()
         ? Quantities.zero
         : new BigNumber(frontendFeeInfo.fee.quantity)
             .dividedBy(ptPriceSell)
-            .integerValue(BigNumber.ROUND_CEIL),
+            .integerValue(BigNumber.ROUND_CEIL)
+            .toString(),
     }
 
     const priceWithSlippage = Quantities.isZero(buyAmountWithSlippage.quantity)