diff --git a/docs/docs/getting-started/choose-provider.md b/docs/docs/getting-started/choose-provider.md
index 57e70046..f9a7159c 100644
--- a/docs/docs/getting-started/choose-provider.md
+++ b/docs/docs/getting-started/choose-provider.md
@@ -22,6 +22,12 @@ const lucid = await Lucid.new(
 );
 ```
 
+```js
+import { Lucid, Koios } from "https://deno.land/x/lucid/mod.ts";
+
+const lucid = await Lucid.new(new Koios("Preprod"), "Preprod");
+```
+
 ### Kupmios
 
 Kupmios is a mix of [Ogmios](https://ogmios.dev/) and
@@ -54,6 +60,19 @@ const lucid = await Lucid.new(
 );
 ```
 
+### Koios
+
+```js
+import { Lucid, Koios } from "https://deno.land/x/lucid/mod.ts";
+
+const lucid = await Lucid.new(
+  new Koios(
+    "https://prepod.koios.rest/api/v0", // For MAINNET: "https://api.koios.rest/api/v0".
+  ),
+  "Preprod", // For MAINNET: "Mainnet".
+);
+```
+
 ### Custom
 
 Lucid may add more providers in the future, but you also have the option to
diff --git a/docs/index.yml b/docs/index.yml
index a7888682..6baf9868 100644
--- a/docs/index.yml
+++ b/docs/index.yml
@@ -135,6 +135,11 @@ usage:
         ),
       );
       ```
+      ```js { title="koios.js" }
+      import { Lucid, Koios } from "https://deno.land/x/lucid/mod.ts"
+
+      const lucid = await Lucid.new(new Koios("Preprod"), "Preprod");
+      ```
       ```js { title="kupmios.js" }
       import { Lucid, Kupmios } from "https://deno.land/x/lucid/mod.ts"
 
diff --git a/src/provider/koios.ts b/src/provider/koios.ts
new file mode 100644
index 00000000..3b121814
--- /dev/null
+++ b/src/provider/koios.ts
@@ -0,0 +1,276 @@
+import {applyDoubleCborEncoding, fromHex, fromUnit} from "../utils/utils.ts";
+import {
+    Address,
+    Assets,
+    Credential,
+    Datum,
+    DatumHash,
+    Delegation,
+    OutRef,
+    ProtocolParameters,
+    Provider,
+    RewardAddress,
+    Transaction,
+    TxHash,
+    Unit,
+    UTxO,
+} from "../types/mod.ts";
+
+export class Koios implements Provider {
+
+    private readonly baseUrl: string
+
+    constructor(baseUrl: string) {
+        this.baseUrl = baseUrl
+    }
+
+    async getProtocolParameters(): Promise<ProtocolParameters> {
+        const result = await fetch(`${this.baseUrl}/epoch_params?limit=1`).then((res) => res.json());
+
+        return {
+            minFeeA: parseInt(result[0].min_fee_a),
+            minFeeB: parseInt(result[0].min_fee_b),
+            maxTxSize: parseInt(result[0].max_tx_size),
+            maxValSize: parseInt(result[0].max_val_size),
+            keyDeposit: BigInt(result[0].key_deposit),
+            poolDeposit: BigInt(result[0].pool_deposit),
+            priceMem: parseFloat(result[0].price_mem),
+            priceStep: parseFloat(result[0].price_step),
+            maxTxExMem: BigInt(result[0].max_tx_ex_mem),
+            maxTxExSteps: BigInt(result[0].max_tx_ex_steps),
+            coinsPerUtxoByte: BigInt(result[0].coins_per_utxo_size),
+            collateralPercentage: parseInt(result[0].collateral_percent),
+            maxCollateralInputs: parseInt(result[0].max_collateral_inputs),
+            costModels: JSON.parse(result[0].cost_models),
+        };
+    }
+
+    async getUtxos(addressOrCredential: Address | Credential): Promise<UTxO[]> {
+        if (typeof addressOrCredential === "string") {
+            const body = {
+                '_addresses': [addressOrCredential]
+            }
+            const result: KoiosAddressInfoResponse = await fetch(`${this.baseUrl}/address_info`, {
+                headers: {
+                    Accept: 'application/json',
+                    'Content-Type': 'application/json'
+                },
+                method: "POST",
+                body: JSON.stringify(body)
+            }).then((res: Response) => res.json());
+            if (Array.isArray(result) && result.length > 0 && result[0].utxo_set && result[0].utxo_set.length > 0) {
+                return (await this.koiosUtxosToUtxos(result[0].utxo_set, result[0].address))
+            } else {
+                return []
+            }
+        } else {
+            throw Error('getUtxos by Credential Type is not supported in Koios yet.')
+        }
+    }
+
+    private async koiosUtxosToUtxos(result: Array<KoiosUTxO>, address?: string): Promise<UTxO[]> {
+        return (await Promise.all(
+            result.map((r: KoiosUTxO) => ({
+                txHash: r.tx_hash,
+                outputIndex: r.tx_index,
+                assets: (() => {
+                    const a: Assets = {};
+                    r.asset_list.forEach((am: KoiosAsset) => {
+                        a[am.policy_id + am.asset_name] = BigInt(am.quantity);
+                    });
+                    return a;
+                })(),
+                address: address,
+                datumHash: !r.inline_datum ? r.datum_hash : undefined,
+                datum: r.inline_datum,
+                scriptRef: {
+                    type: r.reference_script ? r.reference_script.type : null,
+                    script: r.reference_script ? applyDoubleCborEncoding(r.reference_script.bytes) : null
+                },
+            })),
+        )) as UTxO[];
+    }
+
+    async getUtxosWithUnit(addressOrCredential: Address | Credential, unit: Unit): Promise<UTxO[]> {
+        if (typeof addressOrCredential === "string") {
+            const utxos = await this.getUtxos(addressOrCredential);
+            if (utxos && utxos.length > 0) {
+                return utxos.filter((utxo): utxo is UTxO => {
+                    const keys = Object.keys(utxo.assets)
+                    return keys.length > 0 && keys.includes(unit)
+                })
+            } else {
+                return []
+            }
+        } else {
+            throw Error('getUtxosWithUnit by Credential Type is not supported in Koios yet.')
+        }
+    }
+
+    async getUtxoByUnit(unit: Unit): Promise<UTxO> {
+        let {policyId, assetName} = fromUnit(unit)
+        assetName = String(assetName)
+        const assetAddresses = await fetch(`${this.baseUrl}/asset_addresses?_asset_policy=${policyId}&_asset_name=${assetName}`)
+                .then((res: Response) => res.json());
+        if (Array.isArray(assetAddresses) && assetAddresses.length > 0) {
+            if (assetAddresses.length > 1) {
+                throw new Error("Unit needs to be an NFT or only held by one address.");
+            }
+            const utxos: UTxO[] = await this.getUtxos(assetAddresses[0].payment_address)
+            const result = utxos.find<UTxO>((utxo): utxo is UTxO => {
+                const keys = Object.keys(utxo.assets)
+                return keys.length > 0 && keys.includes(unit)
+            })
+            if (result) {
+                return result
+            }
+        }
+        throw new Error("Unit not found.");
+    }
+
+    async getUtxosByOutRef(outRefs: OutRef[]): Promise<UTxO[]> {
+        const utxos = []
+        const body = {
+            '_tx_hashes': [...new Set(outRefs.map((outRef) => outRef.txHash))]
+        }
+        const result = await fetch(`${this.baseUrl}/tx_utxos`, {
+            headers: {
+                Accept: 'application/json',
+                'Content-Type': 'application/json'
+            },
+            method: "POST",
+            body: JSON.stringify(body)
+        }).then((res: Response) => res.json());
+        if (Array.isArray(result) && result.length > 0) {
+            for (const utxo of result) {
+                if (utxo.outputs && utxo.outputs.length > 0) {
+                    utxos.push(await this.koiosUtxosToUtxos(utxo.outputs))
+                }
+            }
+            return utxos.reduce((acc, utxos) => acc.concat(utxos), []).filter((utxo) =>
+                outRefs.some((outRef) =>
+                    utxo.txHash === outRef.txHash && utxo.outputIndex === outRef.outputIndex
+                )
+            );
+        } else {
+            return []
+        }
+    }
+
+    async getDelegation(rewardAddress: RewardAddress): Promise<Delegation> {
+        const body = {
+            '_stake_addresses': [rewardAddress]
+        }
+        const result = await fetch(`${this.baseUrl}/account_info`, {
+            headers: {
+                Accept: 'application/json',
+                'Content-Type': 'application/json'
+            },
+            method: "POST",
+            body: JSON.stringify(body)
+        }).then((res: Response) => res.json());
+        if (Array.isArray(result) && result.length > 0) {
+            return {
+                poolId: result[0].delegated_pool || null,
+                rewards: BigInt(result[0].rewards_available),
+            }
+        } else {
+            throw new Error("No Delegation Found by Reward Address");
+        }
+    }
+
+    async getDatum(datumHash: DatumHash): Promise<Datum> {
+        const body = {
+            '_datum_hashes': [datumHash]
+        }
+        const datum = await fetch(`${this.baseUrl}/datum_info`, {
+            headers: {
+                Accept: 'application/json',
+                'Content-Type': 'application/json'
+            },
+            method: "POST",
+            body: JSON.stringify(body)
+        }).then((res: Response) => res.json());
+        if (Array.isArray(datum) && datum.length > 0) {
+            return datum[0].bytes
+        } else {
+            throw new Error("No Datum Found by Datum Hash");
+        }
+    }
+
+    awaitTx(txHash: TxHash, checkInterval = 3000): Promise<boolean> {
+        return new Promise((res) => {
+            const confirmation = setInterval(async () => {
+                const body = {
+                    '_tx_hashes': [txHash]
+                }
+                const result = await fetch(`${this.baseUrl}/tx_info`, {
+                    headers: {
+                        Accept: 'application/json',
+                        'Content-Type': 'application/json'
+                    },
+                    method: "POST",
+                    body: JSON.stringify(body)
+                }).then((res: Response) => res.json());
+                if (Array.isArray(result) && result.length > 0) {
+                    clearInterval(confirmation);
+                    await new Promise((res) => setTimeout(() => res(1), 1000));
+                    return res(true)
+                }
+            }, checkInterval);
+        });
+    }
+
+    async submitTx(tx: Transaction): Promise<TxHash> {
+        const result = await fetch(`${this.baseUrl}/tx_info`, {
+            headers: {
+                Accept: 'application/json',
+                'Content-Type': 'application/cbor'
+            },
+            method: "POST",
+            body: fromHex(tx)
+        }).then((res: Response) => res.json())
+        if (!result || result.error) {
+            if (result?.status_code === 400) throw new Error(result.message);
+            else throw new Error("Could not submit transaction.");
+        }
+        return result
+    }
+}
+
+type KoiosAddressInfoResponse = Array<{
+    address: Address;
+    balance: string;
+    stake_address?: string
+    script_address: string
+    utxo_set: Array<KoiosUTxO>
+}>;
+
+type KoiosUTxO = {
+    tx_hash: string;
+    tx_index: number;
+    block_height?: number;
+    block_time: number;
+    value: string;
+    datum_hash?: string;
+    inline_datum?: {
+        bytes: string;
+        value: object;
+    }
+    reference_script?: {
+        hash: string;
+        size: number;
+        type: string;
+        bytes: string;
+        value?: object;
+    }
+    asset_list: Array<KoiosAsset>
+}
+
+type KoiosAsset = {
+    policy_id: string;
+    asset_name?: string;
+    fingerprint: string;
+    decimals: number;
+    quantity: string;
+};
\ No newline at end of file
diff --git a/src/provider/mod.ts b/src/provider/mod.ts
index 64a82993..3680736b 100644
--- a/src/provider/mod.ts
+++ b/src/provider/mod.ts
@@ -2,3 +2,4 @@ export * from "./blockfrost.ts";
 export * from "./kupmios.ts";
 export * from "./emulator.ts";
 export * from "./maestro.ts";
+export * from "./koios.ts";
diff --git a/tests/koios.test.ts b/tests/koios.test.ts
new file mode 100644
index 00000000..f4307aad
--- /dev/null
+++ b/tests/koios.test.ts
@@ -0,0 +1,92 @@
+import {Koios} from "../src/provider/koios.ts";
+import {Datum, Delegation, ProtocolParameters, UTxO} from "../src/types/types.ts";
+import {assert} from "https://deno.land/std@0.145.0/testing/asserts.ts";
+import {Lucid} from "../src/lucid/lucid.ts";
+
+const koios = new Koios("https://api.koios.rest/api/v0")
+
+Deno.test("getProtocolParameters", async () => {
+    try {
+        const pp: ProtocolParameters = await koios.getProtocolParameters();
+        assert(pp);
+    } catch (e) {
+        console.log(e)
+    }
+});
+
+Deno.test("getUtxos", async () => {
+    try {
+        const utxos: UTxO[] = await koios.getUtxos("addr1qy2jt0qpqz2z2z9zx5w4xemekkce7yderz53kjue53lpqv90lkfa9sgrfjuz6uvt4uqtrqhl2kj0a9lnr9ndzutx32gqleeckv");
+        assert(utxos);
+    } catch (e) {
+        console.log(e)
+    }
+});
+
+Deno.test("getUtxosWithUnit", async () => {
+    try {
+        const utxos: UTxO[] = await koios.getUtxosWithUnit(
+            "addr1q8vaadv0h7atv366u6966u4rft2svjlf5uajy8lkpsgdrc24rnskuetxz2u3m5ac22s3njvftxcl2fc8k8kjr088ge0qpn6xhn",
+            "85152e10643c1440ba2ba817e3dd1faf7bd7296a8b605efd0f0f2d1844696d656e73696f6e426f78202330313739");
+        console.log(utxos)
+        assert(utxos);
+    } catch (e) {
+        console.log(e)
+    }
+});
+
+Deno.test("getUtxoByUnit", async () => {
+    try {
+        const utxo: UTxO = await koios.getUtxoByUnit("85152e10643c1440ba2ba817e3dd1faf7bd7296a8b605efd0f0f2d1844696d656e73696f6e426f78202330313739");
+        assert(utxo);
+    } catch (e) {
+        console.log(e)
+    }
+});
+
+Deno.test("getUtxosByOutRef", async () => {
+    try {
+        const utxos: UTxO[] = await koios.getUtxosByOutRef([{txHash: 'c6ee20549eab1e565a4bed119bb8c7fc2d11cc5ea5e1e25433a34f0175c0bef6', outputIndex: 0}]);
+        assert(utxos);
+    } catch (e) {
+        console.log(e)
+    }
+});
+
+Deno.test("getDelegation", async () => {
+    const lucid = await Lucid.new(koios, "Mainnet");
+    assert(lucid)
+    try {
+        const delegation: Delegation = await lucid.delegationAt('stake1uyrx65wjqjgeeksd8hptmcgl5jfyrqkfq0xe8xlp367kphsckq250');
+        assert(delegation);
+    } catch (e) {
+        console.log(e)
+    }
+});
+
+Deno.test("getDatum", async () => {
+    try {
+        const datum: Datum = await koios.getDatum('818ee3db3bbbd04f9f2ce21778cac3ac605802a4fcb00c8b3a58ee2dafc17d46');
+        assert(datum);
+    } catch (e) {
+        console.log(e)
+    }
+});
+
+Deno.test("awaitTx", async () => {
+    try {
+        const isConfirmed: boolean = await koios.awaitTx('f144a8264acf4bdfe2e1241170969c930d64ab6b0996a4a45237b623f1dd670e');
+        assert(isConfirmed);
+    } catch (e) {
+        console.log(e)
+    }
+});
+
+Deno.test("submitTxBadRequest", async () => {
+    try {
+        const txId: string = await koios.submitTx('80');
+        assert(txId);
+    } catch (e) {
+        console.log(e)
+    }
+});