With more resources to plan a vacation than ever, today’s price sensitive travelers are getting savvier but at times there’s so many things to consider when making a decision. Pulling booking data from millions of guests who used agoda.com in 2016, the Travel Smart study analyzed room prices across the globe. So what did they learn?

The cheapest time to book is at the beginning of the year—particularly in Europe—while destinations in Asia rank cheapest between June and November. May and September proved to be the most expensive period for rooms across the globe but a deeper dive showed that this does not apply to some Asian destinations like Bangkok.

“As one of the world’s largest online travel accommodation booking sites, we have a strong inventory of over 1.3m properties combined with unrivalled traveler insights and destination expertise. We want to ensure our guests book the perfect room for the best value all year round across Asia and beyond,” said John Brown, Chief Operating Officer of agoda.com.

So how much can you actually save? Hotel rooms in Amsterdam, Oslo and Berlin are more than 20% cheaper in January —though one must keep the cold weather that accounts for this dip in prices and pack your woollies accordingly.  But later in the year, the variations can be stark. Visit Berlin in January, and you’ll save up to 70% more compared to prices in September.

If you are prepared to start your end of year holidays a little earlier, you’ll be able to find good deals in cities like Barcelona and Paris in November and December, despite the global average prices peaking at this time. Pay up to 22% less compared to the annual average in Barcelona to experience Christmas festivities like the Fira de Santa Llúcia and Fira de Sagrada Família.

In Asia, hotel room rates are up to 16% cheaper on average in June and September in countries like Thailand, Japan, and Taiwan. Shopaholics should consider traveling to Hong Kong for the summer between June and September, as accommodations are up to 14% cheaper.

Across the globe, the most expensive month for hotel rooms is May, when 88% of markets studied had higher-than-average room rates. While most destinations experience a peak in May, rooms in Hong Kong and Sydney are seen to be cheaper than average. And though September is considered high season in many destinations, it’s a great time to travel to Dubai.

The study looked at booking data for 2016, but certain annual holidays, such as Chinese New Year and Ramadan, and events like the Milan Furniture Fair take place on different dates each year, which will affect rates.

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