Exhibit 99.1

FOR IMMEDIATE RELEASE

MOBILE MINI REPORTS 2011 FOURTH QUARTER RESULTS

Comparable Quarter Increase in Lease Revenues for Fourth Sequential Quarter

Enters Two More New Markets for a Total of 12 in 2011

Extends Maturity and Reduces Interest Rate on Revolving Credit Facility

Tempe, AZ – February 24, 2012 — Mobile Mini, Inc. (NASDAQ GS: MINI) today reported GAAP and non-GAAP financial results for the fourth quarter and year ended December 31, 2011.

Fourth Quarter 2011 Compared to Fourth Quarter 2010

Other Fourth Quarter 2011 Highlights

2011 Compared to 2010

Non-GAAP reconciliation tables are on page 7, and show the nearest comparable GAAP results to the Non-GAAP results.

Business Overview

Mobile Mini’s Chairman, President & CEO, Steven Bunger stated, “Building upon the favorable performance of the first nine months, 2011 ended on an especially strong note. The top line growth in the final quarter was almost entirely due to an 11.5% increase in comparable quarter lease revenues, furthering the momentum generated when 2011 first, second and third quarter lease revenues rose 3.6%, 7.6% and 9.3% over the respective 2010 quarters. Improvements in utilization and yield drove the comparable quarter increase in lease revenues. Average utilization rose to 61.0% from 55.5% in the final quarter of 2010, as units on rent continued to increase in both North America and Europe. Beyond an improving economic environment, the gains in utilization reflect the opening of new locations in North America, the repositioning of lease assets to these and other high demand locations, and very strong holiday season rentals in 2011 versus 2010. The improvement in lease revenues, as noted, was also due to yield, which was 5.7% ahead of the fourth quarter of 2010 due to increased trucking revenues and a year-over-year average rental rate increase of 2.2%.”

Mr. Bunger pointed out, “We have been investing in the future growth of our business, most notably by entering 12 new markets during 2011 including two acquisitions, just prior to year-end, one in Calgary, Alberta and one in Huntsville, AL. To establish the Calgary branch, our fourth location in Canada, we acquired the largest portable storage operator in that area. For both the Calgary branch and the Huntsville operational yard, we purchased revenue-generating lease fleets, enabling us to forego the majority of start-up expenses in these new markets. Our 2011 locations have been ramping up units on lease and performing according to plan.”

He continued, “As a result of an increase in utilization coupled with our operating leverage, our non-GAAP EBITDA margins increased 2.0 percentage points from 36.8% in the 2011 third quarter to 38.8% for the fourth quarter. On a year-over-year basis, the combination of more deliveries which have lower associated margins, higher repair and maintenance expense, long-distance fleet repositioning, as well as entering 12 new markets, slightly depressed Mobile Mini’s fourth quarter non-GAAP EBITDA margin to 38.8% from last year’s 40.0%. We see these investments as positive signs that our growth initiatives are well underway.”

Mark Funk, Mobile Mini’s Executive Vice President & CFO noted, “As of 2011 year-end, we generated free cash flow for 16 consecutive quarters. Fourth quarter free cash flow totaled $16.4 million bringing the 2011 total to $80.0 million. Cash flow from operations of $21.2 million enhanced our ability to pay down an additional $12.0 million of debt in the fourth quarter, bringing the full year’s debt pay down to $75.3 million after payment of a $1.1 million call premium related to redeeming the remaining $22.3 million of previously outstanding MSG Senior Notes. Since the acquisition of Mobile Storage Group in mid-2008, we have generated free cash flow of $258.5 million and paid down $235.3 million of debt. As a result of our senior note refinancing in November 2010, our 2011 debt pay down and lower interest rates, our 2011 interest expense has been reduced by 18% or $10.1 million compared to 2010.”

Extends Revolving Credit Agreement

Mobile Mini also announced that it has extended the maturity of its asset-based revolving credit facility (“ABL”) to February 22, 2017, or five years from closing. The previous asset-based revolving credit facility would have matured on June 27, 2013. At closing, the interest rate on borrowings under the new agreement is LIBOR plus 2.25%, reduced from LIBOR plus 2.75% under the prior agreement. The maximum principal amount has increased to $900 million from $850 million. The other terms of the ABL credit agreement also provide additional flexibility compared to the prior agreement.”

According to Mr. Funk, “Based upon Mobile Mini’s outstanding borrowings at December 31, 2011, the new lower interest rate would have produced annualized savings of over $1.7 million. With a more favorable interest rate, greater borrowing availability and a five year maturity, the new facility strengthens Mobile Mini’s capital structure, enhances our liquidity and saves us interest expense.”

He continued, “We appreciate the continued support of Deutsche Bank AG, Bank of America, JP Morgan and our other lenders for their confidence in our growth strategy.”

Outlook

Mr. Bunger went on to say, “We plan to add at least eight new markets this year, following our entry into 12 new markets in 2011, and three in 2010. The first of this year was opened in Rochester, NY and with this new operational yard, our reach extends to another major New York market. During 2012, we are expanding our focus on the consumer market. At present, we offer storage to consumers at five of our existing locations. This year we plan to add to our product offering including providing warehouse storage in seven of our current markets.”

Mr. Bunger concluded, “As we continue to build on our current momentum, we expect that Mobile Mini will achieve gains in revenues, lease revenues, EBITDA and net income in 2012. We are likewise confident that the actions undertaken to strengthen, grow and expand our operations, supported by a strong and flexible financial framework, will continue to have enduring and cumulative benefits.”

EBITDA, EBITDA margin, non-GAAP SG&A and free cash flow are non-GAAP financial measures as defined by Securities and Exchange Commission (“SEC”) rules. Reconciliations of EBITDA, EBITDA margin, and free cash flow to the most directly comparable GAAP financial measures can be found later in this release.

Conference Call

Mobile Mini will host a conference call today, Friday, February 24, 2012 at 12 noon ET to review these results. To listen to the call live, dial (201) 493-6739 and ask for the Mobile Mini Conference Call or go to www.mobilemini.com and click on the Investors section. Additionally, a slide presentation that will accompany the call will be posted at www.mobilemini.com on the Investors section and will be available in advance and after the call. We will also post the reconciliation of non-GAAP financial measures used in the slide show to the most directly comparable GAAP financial measures. Please go to the website 15 minutes early to download and install any necessary audio software. If you are unable to listen live, a replay of the conference call can be accessed for approximately 14 days after the call at Mobile Mini’s website.

Mobile Mini, Inc. is the world’s leading provider of portable storage solutions through its total lease fleet of approximately 237,600 portable storage containers and office units with 134 locations in the U.S., United Kingdom, Canada and The Netherlands. Mobile Mini is included on the Russell 2000^® and 3000^® Indexes and the S&P Small Cap Index.

This news release contains forward-looking statements, particularly regarding growth, free cash flow, ability to enter new markets, increase in utilization, the ability to strengthen, grow and expand our operations, and increasing debt pay down, which involve risks and uncertainties that could cause actual results to differ materially from those currently anticipated. Risks and uncertainties that may affect future results include those that are described from time to time in the Company’s SEC filings. These forward-looking statements represent the judgment of the Company, as of the date of this release, and Mobile Mini disclaims any intent or obligation to update forward-looking statements.

(See Accompanying Tables)

Mobile Mini, Inc. Condensed Consolidated Statements of Income

(Unaudited)/(in 000’s except per share data)/(includes effects of rounding)

Mobile Mini, Inc. Condensed Consolidated Statements of Income

(Unaudited)/(in 000’s except per share data)/(includes effects of rounding)

This press release includes the financial measures “EBITDA”, “EBITDA margin”, “non-GAAP SG&A” and “free cash flow”. These measurements are deemed “non-GAAP financial measures” under rules of the SEC, including Regulation G. This non-GAAP financial information may be determined or calculated differently by other companies.

EBITDA is defined as net income before interest expense, income taxes, depreciation and amortization, and if applicable, debt restructuring or extinguishment costs. We typically further adjust EBITDA to ignore the effect of what we consider transactions or events not related to our core business to arrive at non-GAAP EBITDA in the reconciliation below. The GAAP financial measure that is most directly comparable to EBITDA is net cash provided by operating activities. EBITDA margin is calculated by dividing consolidated EBITDA by total revenues. The GAAP financial measure that is most directly comparable to EBITDA margin is operating margin, which represents operating income divided by revenues. We present EBITDA and EBITDA margin because we believe they provide useful information regarding our ability to meet our future debt payment requirements, capital expenditures and working capital requirements and they provide an overall evaluation of our financial condition. In addition, EBITDA is a component of certain financial covenants under our revolving credit facility and is used to determine our available borrowing ability and the interest rate. We include EBITDA in the earnings announcement to provide transparency to investors. EBITDA has certain limitations as an analytical tool and should not be used as a substitute for net income, cash flows, or other consolidated income or cash flow data prepared in accordance with GAAP or as a measure of our profitability or our liquidity. EBITDA margin is presented along with the operating margin so as not to imply that more emphasis should be placed on it than the corresponding GAAP measure.

Free cash flow is defined as net cash provided by operating activities, less net cash used in investing activities, excluding acquisitions. Free cash flow is a non-GAAP financial measure and is not intended to replace net cash provided by operating activities, the most directly comparable GAAP financial measure. We present free cash flow because we believe it provides useful information regarding our liquidity and ability to meet our short-term obligations. In particular, free cash flow indicates the amount of cash available after capital expenditures for, among other things, investments in the Company’s existing businesses, debt service obligations and strategic acquisitions.

Non-GAAP SG&A permits a comparative assessment of our SG&A expenses by excluding certain one-time expenses to make a more meaningful comparison of our operating performance.

A reconciliation of EBITDA to net cash provided by operating activities and net income to EBITDA and non-GAAP EBITDA, as well as a reconciliation of net cash provided by operating activities to free cash flow, follows. These reconciliations are in thousands and include effects of rounding.

Mobile Mini, Inc.

Condensed Consolidated Balance Sheets

(in 000’s except par value data)

(includes effects of rounding)