More than 150 jobs have been cut at embattled bookseller Booktopia as the company stops taking customer orders.

The major Australian online book retailer entered voluntary administration last week, with customers complaining of being left in the dark about pending orders.

An “urgent assessment” of Booktopia is being undertaken by administrators from McGrathNicol, who are looking to sell all or parts of the business.

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Booktopia suffered a $16.7 million loss for the six months to December 31, following a $3.9 million loss a year ago.

The company recently laid off 50 employees across several departments at its Sydney headquarters and its former CEO stepped down in a major restructure it estimated would save it $6.1 million.

Now, administrators have axed 165 jobs, with just 18 employees left, according to the Sydney Morning Herald.

McGrathNicol confirmed to 7NEWS.com.au the mass redundancies were made soon after administrators were appointed.

Booktopia shares have not traded on the ASX since June 13 while it attempted to secure additional funding.

The company has also stopped taking orders, with customers met with a message stating: “Payment gateway under maintenance, try again later.”

The same applies for customers trying to purchase a book through Angus & Robertson, which is owned by Booktopia.

Social media has been flooded with frustrated shoppers demanding refunds and information on existing orders.

“With Booktopia dying, I’m out over $3k on unfilled orders. This sucks,” one customer said.

Another added: “Well, looks like I’m a creditor of Booktopia. I won’t be receiving my final order — placed three weeks ago and due about now — or a refund. The loss of money is annoying but I wanted those books!”

Much to customers’ dismay, orders placed before Booktopia collapsed will not be fulfilled, according to a letter from administrators on Monday.

Refunds or store credits are also off the cards at this stage.

“The value of the orders placed prior to the administrators’ appointment represent an unsecured claim against Booktopia and you will need to complete a proof of debt form,” administrators said.

“Any return to unsecured creditors will be subject to the outcome of the sale process.

“The administrators are not able to comment on the ability of customers to pursue other avenues for refunds of their orders.

“Individual circumstances may vary in relation to the ability for customers to request a refund from third-party intermediaries.”

McGrathNicol partners Keith Crawford, Matthew Caddy and Damien Pasfield were appointed voluntary administrators on July 3.

“We are urgently engaging with key stakeholders to maximise the prospect of successfully completing a sale or recapitalisation of Booktopia,” Crawford said.

“Our immediate focus is to undertake an assessment of Booktopia’s assets and work alongside employees, suppliers, and customers to secure the best outcome for all parties.”

Expressions of interest in the sale of Booktopia were due Monday, and indicative offers are due by the end of the week.

7NEWS.com.au understands interest has been “very strong”.

Updates are expected to be provided to creditors, including customers.

A creditors’ meeting is due to be held by July 15 and a creditors’ report will be issued by the end of the month.

Customers can contact administrators via booktopiacustomers@mcgrathnicol.com.