diff --git a/packages/core/components/FileList/test/LazilyRenderedThumbnail.test.tsx b/packages/core/components/FileList/test/LazilyRenderedThumbnail.test.tsx
new file mode 100644
index 000000000..e65917d40
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+++ b/packages/core/components/FileList/test/LazilyRenderedThumbnail.test.tsx
@@ -0,0 +1,202 @@
+import { configureMockStore, mergeState } from "@aics/redux-utils";
+import { render } from "@testing-library/react";
+import { expect } from "chai";
+import * as React from "react";
+import { Provider } from "react-redux";
+import * as sinon from "sinon";
+
+import LazilyRenderedThumbnail from "../LazilyRenderedThumbnail";
+import { initialState } from "../../../state";
+import FileSet from "../../../entity/FileSet";
+
+describe("<LazilyRenderedThumbnail />", () => {
+    function makeItemData() {
+        const fileSet = new FileSet();
+        sinon.stub(fileSet, "getFileByIndex").callsFake((index) => {
+            if (index === 0) {
+                return {
+                    annotations: [],
+                    file_id: "abc1230",
+                    file_name: "my_image0.czi",
+                    file_path: "some/path/to/my_image0.czi",
+                    file_size: 1,
+                    thumbnail: "some/path/to/my_image0.jpg",
+                    uploaded: new Date().toISOString(),
+                };
+            }
+            if (index === 9) {
+                return {
+                    annotations: [],
+                    file_id: "abc1239",
+                    file_name: "my_image9.jpg",
+                    file_path: "some/path/to/my_image9.jpg",
+                    file_size: 1,
+                    thumbnail: "",
+                    uploaded: new Date().toISOString(),
+                };
+            }
+            if (index === 25) {
+                return {
+                    annotations: [],
+                    file_id: "abc12325",
+                    file_name: "my_image25.czi",
+                    file_path: "some/path/to/my_image25.czi",
+                    file_size: 1,
+                    thumbnail: "",
+                    uploaded: new Date().toISOString(),
+                };
+            }
+        });
+
+        return {
+            fileSet,
+            measuredWidth: 600,
+            itemCount: 100,
+            onContextMenu: sinon.spy(),
+            onSelect: sinon.spy(),
+        };
+    }
+
+    it("renders thumbnail when file has one specified", () => {
+        // Arrange
+        const state = mergeState(initialState, {});
+        const { store } = configureMockStore({ state });
+
+        // Act
+        const { getByText, getByRole } = render(
+            <Provider store={store}>
+                <LazilyRenderedThumbnail
+                    data={makeItemData()}
+                    rowIndex={0}
+                    columnIndex={0}
+                    style={{}}
+                />
+            </Provider>
+        );
+
+        // Assert
+        // Also checking for proper row/col indexing
+        const thumbnail = getByRole("img");
+        expect(thumbnail.getAttribute("src")).to.include("some/path/to/my_image0.jpg");
+        expect(getByText("my_image0.czi")).to.not.equal(null);
+    });
+
+    it("renders file as thumbnail if file is renderable type", () => {
+        // Arrange
+        const { store } = configureMockStore({ state: initialState });
+
+        // Act
+        const { getByText, getByRole } = render(
+            <Provider store={store}>
+                <LazilyRenderedThumbnail
+                    data={makeItemData()}
+                    rowIndex={1}
+                    columnIndex={4}
+                    style={{}}
+                />
+            </Provider>
+        );
+
+        // Assert
+        // Also confirms proper row/col indexing
+        const thumbnail = getByRole("img");
+        expect(thumbnail.getAttribute("src")).to.include("some/path/to/my_image9.jpg");
+        expect(getByText("my_image9.jpg")).to.not.equal(null);
+    });
+
+    it("renders svg as thumbnail if file has no renderable thumbnail", () => {
+        // Arrange
+        const { store } = configureMockStore({ state: initialState });
+
+        // Act
+        const { getByText, queryByRole } = render(
+            <Provider store={store}>
+                <LazilyRenderedThumbnail
+                    data={makeItemData()}
+                    rowIndex={5}
+                    columnIndex={0}
+                    style={{}}
+                />
+            </Provider>
+        );
+
+        // Assert
+        // Also confirms proper row/col indexing
+        expect(".no-thumbnail").to.exist;
+        expect(".svg").to.exist;
+        expect(queryByRole("img")).not.to.exist;
+        expect(getByText("my_image25.czi")).to.not.equal(null);
+    });
+
+    it("renders a loading indicator when data is not available", () => {
+        // Arrange
+        const { store } = configureMockStore({ state: initialState });
+
+        // Act
+        const { queryByText } = render(
+            <Provider store={store}>
+                <LazilyRenderedThumbnail
+                    data={makeItemData()}
+                    rowIndex={2}
+                    columnIndex={3}
+                    style={{}}
+                />
+            </Provider>
+        );
+
+        // Assert
+        expect(queryByText("my_image")).to.equal(null);
+        expect(queryByText("Loading...")).to.not.equal(null);
+    });
+
+    // We want to be able to render empty cells past the total item count in order to fill the grid
+    it("renders an empty cell if the index is past the total item count", () => {
+        // Arrange
+        const { store } = configureMockStore({ state: initialState });
+
+        // Act
+        const { queryByText } = render(
+            <Provider store={store}>
+                <LazilyRenderedThumbnail
+                    data={makeItemData()}
+                    rowIndex={20}
+                    columnIndex={5}
+                    style={{}}
+                />
+            </Provider>
+        );
+
+        // Assert
+        expect(queryByText("my_image")).to.equal(null);
+        expect(queryByText("Loading...")).to.equal(null);
+    });
+
+    it("renders and indexes correctly with different number of columns", () => {
+        // Arrange
+        const state = {
+            ...initialState,
+            selection: {
+                ...initialState.selection,
+                fileGridColumnCount: 10,
+            },
+        };
+        const { store } = configureMockStore({ state });
+
+        // Act
+        const { getByText } = render(
+            <Provider store={store}>
+                <LazilyRenderedThumbnail
+                    data={makeItemData()}
+                    rowIndex={2}
+                    columnIndex={5}
+                    style={{}}
+                />
+            </Provider>
+        );
+
+        // Assert
+        expect(".no-thumbnail").to.exist;
+        expect(".svg").to.exist;
+        expect(getByText("my_image25.czi")).to.not.equal(null);
+    });
+});