diff --git a/contracts/Marketplace.sol b/contracts/Marketplace.sol
index 2d2e75b..ec5a324 100644
--- a/contracts/Marketplace.sol
+++ b/contracts/Marketplace.sol
@@ -96,6 +96,25 @@ contract Marketplace is Collateral, Proofs {
     require(token.transfer(slot.host, amount), "Payment failed");
   }
 
+  function withdrawFunds(bytes32 requestId) public marketplaceInvariant {
+    Request memory request = requests[requestId];
+    require(block.timestamp > request.expiry, "Request not yet timed out");
+    require(request.client == msg.sender, "Invalid client address");
+    RequestContext storage context = requestContexts[requestId];
+    require(context.state == RequestState.New, "Invalid state");
+
+    uint256 amount = _price(request);
+    funds.sent += amount;
+    funds.balance -= amount;
+    token.transfer(msg.sender, amount);
+    emit FundsWithdrawn(requestId);
+
+    // Update request state to Cancelled. Handle in the withdraw transaction
+    // as there needs to be someone to pay for the gas to update the state
+    context.state = RequestState.Cancelled;
+    emit RequestCancelled(requestId);
+  }
+
   function _host(bytes32 slotId) internal view returns (address) {
     return slots[slotId].host;
   }
@@ -116,8 +135,20 @@ contract Marketplace is Collateral, Proofs {
     return _end(slotId);
   }
 
+  function _price(
+    uint64 numSlots,
+    uint256 duration,
+    uint256 reward) internal pure returns (uint256) {
+
+    return numSlots * duration * reward;
+  }
+
+  function _price(Request memory request) internal pure returns (uint256) {
+    return _price(request.ask.slots, request.ask.duration, request.ask.reward);
+  }
+
   function price(Request calldata request) private pure returns (uint256) {
-    return request.ask.slots * request.ask.duration * request.ask.reward;
+    return _price(request.ask.slots, request.ask.duration, request.ask.reward);
   }
 
   function pricePerSlot(Request memory request) private pure returns (uint256) {
@@ -164,7 +195,8 @@ contract Marketplace is Collateral, Proofs {
     New,        // [default] waiting to fill slots
     Started,    // all slots filled, accepting regular proofs
     Cancelled,  // not enough slots filled before expiry
-    Finished    // successfully completed
+    Finished,   // successfully completed
+    Failed      // too many nodes have failed to provide proofs, data lost
   }
 
   struct RequestContext {
@@ -184,6 +216,8 @@ contract Marketplace is Collateral, Proofs {
     uint256 indexed slotIndex,
     bytes32 indexed slotId
   );
+  event RequestCancelled(bytes32 requestId);
+  event FundsWithdrawn(bytes32 requestId);
 
   modifier marketplaceInvariant() {
     MarketplaceFunds memory oldFunds = funds;
diff --git a/test/Marketplace.test.js b/test/Marketplace.test.js
index a51f59c..761563e 100644
--- a/test/Marketplace.test.js
+++ b/test/Marketplace.test.js
@@ -4,6 +4,7 @@ const { expect } = require("chai")
 const { exampleRequest } = require("./examples")
 const { now, hours } = require("./time")
 const { requestId, slotId, askToArray } = require("./ids")
+const { waitUntilExpired } = require("./marketplace")
 const { price, pricePerSlot } = require("./price")
 const {
   snapshot,
@@ -258,5 +259,77 @@ describe("Marketplace", function () {
       }
       await expect(await marketplace.state(slot.request)).to.equal(1)
     })
+    it("fails when all slots are already filled", async function () {
+      const lastSlot = request.ask.slots - 1
+      for (let i = 0; i <= lastSlot; i++) {
+        await marketplace.fillSlot(slot.request, i, proof)
+      }
+      await expect(
+        marketplace.fillSlot(slot.request, lastSlot, proof)
+      ).to.be.revertedWith("Invalid state")
+    })
+  })
+
+  describe("withdrawing funds", function () {
+    beforeEach(async function () {
+      switchAccount(client)
+      await token.approve(marketplace.address, price(request))
+      await marketplace.requestStorage(request)
+      switchAccount(host)
+      await token.approve(marketplace.address, collateral)
+      await marketplace.deposit(collateral)
+    })
+
+    it("rejects withdraw when request not yet timed out", async function () {
+      switchAccount(client)
+      await expect(marketplace.withdrawFunds(slot.request)).to.be.revertedWith(
+        "Request not yet timed out"
+      )
+    })
+
+    it("rejects withdraw when wrong account used", async function () {
+      await waitUntilExpired(request.expiry)
+      await expect(marketplace.withdrawFunds(slot.request)).to.be.revertedWith(
+        "Invalid client address"
+      )
+    })
+
+    it("rejects withdraw when in wrong state", async function () {
+      // fill all slots, should change state to RequestState.Started
+      const lastSlot = request.ask.slots - 1
+      for (let i = 0; i <= lastSlot; i++) {
+        await marketplace.fillSlot(slot.request, i, proof)
+      }
+      await waitUntilExpired(request.expiry)
+      switchAccount(client)
+      await expect(marketplace.withdrawFunds(slot.request)).to.be.revertedWith(
+        "Invalid state"
+      )
+    })
+
+    it("emits event once funds are withdrawn", async function () {
+      await waitUntilExpired(request.expiry)
+      switchAccount(client)
+      await expect(marketplace.withdrawFunds(slot.request))
+        .to.emit(marketplace, "FundsWithdrawn")
+        .withArgs(requestId(request))
+    })
+
+    it("emits event once request is cancelled", async function () {
+      await waitUntilExpired(request.expiry)
+      switchAccount(client)
+      await expect(marketplace.withdrawFunds(slot.request))
+        .to.emit(marketplace, "RequestCancelled")
+        .withArgs(requestId(request))
+    })
+
+    it("withdraws to the client", async function () {
+      await waitUntilExpired(request.expiry)
+      switchAccount(client)
+      const startBalance = await token.balanceOf(client.address)
+      await marketplace.withdrawFunds(slot.request)
+      const endBalance = await token.balanceOf(client.address)
+      expect(endBalance - startBalance).to.equal(price(request))
+    })
   })
 })
diff --git a/test/marketplace.js b/test/marketplace.js
new file mode 100644
index 0000000..d4bc229
--- /dev/null
+++ b/test/marketplace.js
@@ -0,0 +1,5 @@
+async function waitUntilExpired(expiry) {
+  await ethers.provider.send("hardhat_mine", [ethers.utils.hexValue(expiry)])
+}
+
+module.exports = { waitUntilExpired }